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diff --git a/vendor/image/src/codecs/webp/vp8.rs b/vendor/image/src/codecs/webp/vp8.rs
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+//! An implementation of the VP8 Video Codec
+//!
+//! This module contains a partial implementation of the
+//! VP8 video format as defined in RFC-6386.
+//!
+//! It decodes Keyframes only.
+//! VP8 is the underpinning of the WebP image format
+//!
+//! # Related Links
+//! * [rfc-6386](http://tools.ietf.org/html/rfc6386) - The VP8 Data Format and Decoding Guide
+//! * [VP8.pdf](http://static.googleusercontent.com/media/research.google.com/en//pubs/archive/37073.pdf) - An overview of
+//! of the VP8 format
+//!
+
+use byteorder::{LittleEndian, ReadBytesExt};
+use std::convert::TryInto;
+use std::default::Default;
+use std::io::Read;
+use std::{cmp, error, fmt};
+
+use super::loop_filter;
+use super::transform;
+use crate::error::{
+ DecodingError, ImageError, ImageResult, UnsupportedError, UnsupportedErrorKind,
+};
+use crate::image::ImageFormat;
+
+use crate::utils::clamp;
+
+const MAX_SEGMENTS: usize = 4;
+const NUM_DCT_TOKENS: usize = 12;
+
+// Prediction modes
+const DC_PRED: i8 = 0;
+const V_PRED: i8 = 1;
+const H_PRED: i8 = 2;
+const TM_PRED: i8 = 3;
+const B_PRED: i8 = 4;
+
+const B_DC_PRED: i8 = 0;
+const B_TM_PRED: i8 = 1;
+const B_VE_PRED: i8 = 2;
+const B_HE_PRED: i8 = 3;
+const B_LD_PRED: i8 = 4;
+const B_RD_PRED: i8 = 5;
+const B_VR_PRED: i8 = 6;
+const B_VL_PRED: i8 = 7;
+const B_HD_PRED: i8 = 8;
+const B_HU_PRED: i8 = 9;
+
+// Prediction mode enum
+#[repr(i8)]
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+enum LumaMode {
+ /// Predict DC using row above and column to the left.
+ DC = DC_PRED,
+
+ /// Predict rows using row above.
+ V = V_PRED,
+
+ /// Predict columns using column to the left.
+ H = H_PRED,
+
+ /// Propagate second differences.
+ TM = TM_PRED,
+
+ /// Each Y subblock is independently predicted.
+ B = B_PRED,
+}
+
+#[repr(i8)]
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+enum ChromaMode {
+ /// Predict DC using row above and column to the left.
+ DC = DC_PRED,
+
+ /// Predict rows using row above.
+ V = V_PRED,
+
+ /// Predict columns using column to the left.
+ H = H_PRED,
+
+ /// Propagate second differences.
+ TM = TM_PRED,
+}
+
+#[repr(i8)]
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+enum IntraMode {
+ DC = B_DC_PRED,
+ TM = B_TM_PRED,
+ VE = B_VE_PRED,
+ HE = B_HE_PRED,
+ LD = B_LD_PRED,
+ RD = B_RD_PRED,
+ VR = B_VR_PRED,
+ VL = B_VL_PRED,
+ HD = B_HD_PRED,
+ HU = B_HU_PRED,
+}
+
+type Prob = u8;
+
+static SEGMENT_ID_TREE: [i8; 6] = [2, 4, -0, -1, -2, -3];
+
+// Section 11.2
+// Tree for determining the keyframe luma intra prediction modes:
+static KEYFRAME_YMODE_TREE: [i8; 8] = [-B_PRED, 2, 4, 6, -DC_PRED, -V_PRED, -H_PRED, -TM_PRED];
+
+// Default probabilities for decoding the keyframe luma modes
+static KEYFRAME_YMODE_PROBS: [Prob; 4] = [145, 156, 163, 128];
+
+// Tree for determining the keyframe B_PRED mode:
+static KEYFRAME_BPRED_MODE_TREE: [i8; 18] = [
+ -B_DC_PRED, 2, -B_TM_PRED, 4, -B_VE_PRED, 6, 8, 12, -B_HE_PRED, 10, -B_RD_PRED, -B_VR_PRED,
+ -B_LD_PRED, 14, -B_VL_PRED, 16, -B_HD_PRED, -B_HU_PRED,
+];
+
+// Probabilities for the BPRED_MODE_TREE
+static KEYFRAME_BPRED_MODE_PROBS: [[[u8; 9]; 10]; 10] = [
+ [
+ [231, 120, 48, 89, 115, 113, 120, 152, 112],
+ [152, 179, 64, 126, 170, 118, 46, 70, 95],
+ [175, 69, 143, 80, 85, 82, 72, 155, 103],
+ [56, 58, 10, 171, 218, 189, 17, 13, 152],
+ [144, 71, 10, 38, 171, 213, 144, 34, 26],
+ [114, 26, 17, 163, 44, 195, 21, 10, 173],
+ [121, 24, 80, 195, 26, 62, 44, 64, 85],
+ [170, 46, 55, 19, 136, 160, 33, 206, 71],
+ [63, 20, 8, 114, 114, 208, 12, 9, 226],
+ [81, 40, 11, 96, 182, 84, 29, 16, 36],
+ ],
+ [
+ [134, 183, 89, 137, 98, 101, 106, 165, 148],
+ [72, 187, 100, 130, 157, 111, 32, 75, 80],
+ [66, 102, 167, 99, 74, 62, 40, 234, 128],
+ [41, 53, 9, 178, 241, 141, 26, 8, 107],
+ [104, 79, 12, 27, 217, 255, 87, 17, 7],
+ [74, 43, 26, 146, 73, 166, 49, 23, 157],
+ [65, 38, 105, 160, 51, 52, 31, 115, 128],
+ [87, 68, 71, 44, 114, 51, 15, 186, 23],
+ [47, 41, 14, 110, 182, 183, 21, 17, 194],
+ [66, 45, 25, 102, 197, 189, 23, 18, 22],
+ ],
+ [
+ [88, 88, 147, 150, 42, 46, 45, 196, 205],
+ [43, 97, 183, 117, 85, 38, 35, 179, 61],
+ [39, 53, 200, 87, 26, 21, 43, 232, 171],
+ [56, 34, 51, 104, 114, 102, 29, 93, 77],
+ [107, 54, 32, 26, 51, 1, 81, 43, 31],
+ [39, 28, 85, 171, 58, 165, 90, 98, 64],
+ [34, 22, 116, 206, 23, 34, 43, 166, 73],
+ [68, 25, 106, 22, 64, 171, 36, 225, 114],
+ [34, 19, 21, 102, 132, 188, 16, 76, 124],
+ [62, 18, 78, 95, 85, 57, 50, 48, 51],
+ ],
+ [
+ [193, 101, 35, 159, 215, 111, 89, 46, 111],
+ [60, 148, 31, 172, 219, 228, 21, 18, 111],
+ [112, 113, 77, 85, 179, 255, 38, 120, 114],
+ [40, 42, 1, 196, 245, 209, 10, 25, 109],
+ [100, 80, 8, 43, 154, 1, 51, 26, 71],
+ [88, 43, 29, 140, 166, 213, 37, 43, 154],
+ [61, 63, 30, 155, 67, 45, 68, 1, 209],
+ [142, 78, 78, 16, 255, 128, 34, 197, 171],
+ [41, 40, 5, 102, 211, 183, 4, 1, 221],
+ [51, 50, 17, 168, 209, 192, 23, 25, 82],
+ ],
+ [
+ [125, 98, 42, 88, 104, 85, 117, 175, 82],
+ [95, 84, 53, 89, 128, 100, 113, 101, 45],
+ [75, 79, 123, 47, 51, 128, 81, 171, 1],
+ [57, 17, 5, 71, 102, 57, 53, 41, 49],
+ [115, 21, 2, 10, 102, 255, 166, 23, 6],
+ [38, 33, 13, 121, 57, 73, 26, 1, 85],
+ [41, 10, 67, 138, 77, 110, 90, 47, 114],
+ [101, 29, 16, 10, 85, 128, 101, 196, 26],
+ [57, 18, 10, 102, 102, 213, 34, 20, 43],
+ [117, 20, 15, 36, 163, 128, 68, 1, 26],
+ ],
+ [
+ [138, 31, 36, 171, 27, 166, 38, 44, 229],
+ [67, 87, 58, 169, 82, 115, 26, 59, 179],
+ [63, 59, 90, 180, 59, 166, 93, 73, 154],
+ [40, 40, 21, 116, 143, 209, 34, 39, 175],
+ [57, 46, 22, 24, 128, 1, 54, 17, 37],
+ [47, 15, 16, 183, 34, 223, 49, 45, 183],
+ [46, 17, 33, 183, 6, 98, 15, 32, 183],
+ [65, 32, 73, 115, 28, 128, 23, 128, 205],
+ [40, 3, 9, 115, 51, 192, 18, 6, 223],
+ [87, 37, 9, 115, 59, 77, 64, 21, 47],
+ ],
+ [
+ [104, 55, 44, 218, 9, 54, 53, 130, 226],
+ [64, 90, 70, 205, 40, 41, 23, 26, 57],
+ [54, 57, 112, 184, 5, 41, 38, 166, 213],
+ [30, 34, 26, 133, 152, 116, 10, 32, 134],
+ [75, 32, 12, 51, 192, 255, 160, 43, 51],
+ [39, 19, 53, 221, 26, 114, 32, 73, 255],
+ [31, 9, 65, 234, 2, 15, 1, 118, 73],
+ [88, 31, 35, 67, 102, 85, 55, 186, 85],
+ [56, 21, 23, 111, 59, 205, 45, 37, 192],
+ [55, 38, 70, 124, 73, 102, 1, 34, 98],
+ ],
+ [
+ [102, 61, 71, 37, 34, 53, 31, 243, 192],
+ [69, 60, 71, 38, 73, 119, 28, 222, 37],
+ [68, 45, 128, 34, 1, 47, 11, 245, 171],
+ [62, 17, 19, 70, 146, 85, 55, 62, 70],
+ [75, 15, 9, 9, 64, 255, 184, 119, 16],
+ [37, 43, 37, 154, 100, 163, 85, 160, 1],
+ [63, 9, 92, 136, 28, 64, 32, 201, 85],
+ [86, 6, 28, 5, 64, 255, 25, 248, 1],
+ [56, 8, 17, 132, 137, 255, 55, 116, 128],
+ [58, 15, 20, 82, 135, 57, 26, 121, 40],
+ ],
+ [
+ [164, 50, 31, 137, 154, 133, 25, 35, 218],
+ [51, 103, 44, 131, 131, 123, 31, 6, 158],
+ [86, 40, 64, 135, 148, 224, 45, 183, 128],
+ [22, 26, 17, 131, 240, 154, 14, 1, 209],
+ [83, 12, 13, 54, 192, 255, 68, 47, 28],
+ [45, 16, 21, 91, 64, 222, 7, 1, 197],
+ [56, 21, 39, 155, 60, 138, 23, 102, 213],
+ [85, 26, 85, 85, 128, 128, 32, 146, 171],
+ [18, 11, 7, 63, 144, 171, 4, 4, 246],
+ [35, 27, 10, 146, 174, 171, 12, 26, 128],
+ ],
+ [
+ [190, 80, 35, 99, 180, 80, 126, 54, 45],
+ [85, 126, 47, 87, 176, 51, 41, 20, 32],
+ [101, 75, 128, 139, 118, 146, 116, 128, 85],
+ [56, 41, 15, 176, 236, 85, 37, 9, 62],
+ [146, 36, 19, 30, 171, 255, 97, 27, 20],
+ [71, 30, 17, 119, 118, 255, 17, 18, 138],
+ [101, 38, 60, 138, 55, 70, 43, 26, 142],
+ [138, 45, 61, 62, 219, 1, 81, 188, 64],
+ [32, 41, 20, 117, 151, 142, 20, 21, 163],
+ [112, 19, 12, 61, 195, 128, 48, 4, 24],
+ ],
+];
+
+// Section 11.4 Tree for determining macroblock the chroma mode
+static KEYFRAME_UV_MODE_TREE: [i8; 6] = [-DC_PRED, 2, -V_PRED, 4, -H_PRED, -TM_PRED];
+
+// Probabilities for determining macroblock mode
+static KEYFRAME_UV_MODE_PROBS: [Prob; 3] = [142, 114, 183];
+
+// Section 13.4
+type TokenProbTables = [[[[Prob; NUM_DCT_TOKENS - 1]; 3]; 8]; 4];
+
+// Probabilities that a token's probability will be updated
+static COEFF_UPDATE_PROBS: TokenProbTables = [
+ [
+ [
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ ],
+ [
+ [176, 246, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [223, 241, 252, 255, 255, 255, 255, 255, 255, 255, 255],
+ [249, 253, 253, 255, 255, 255, 255, 255, 255, 255, 255],
+ ],
+ [
+ [255, 244, 252, 255, 255, 255, 255, 255, 255, 255, 255],
+ [234, 254, 254, 255, 255, 255, 255, 255, 255, 255, 255],
+ [253, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ ],
+ [
+ [255, 246, 254, 255, 255, 255, 255, 255, 255, 255, 255],
+ [239, 253, 254, 255, 255, 255, 255, 255, 255, 255, 255],
+ [254, 255, 254, 255, 255, 255, 255, 255, 255, 255, 255],
+ ],
+ [
+ [255, 248, 254, 255, 255, 255, 255, 255, 255, 255, 255],
+ [251, 255, 254, 255, 255, 255, 255, 255, 255, 255, 255],
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ ],
+ [
+ [255, 253, 254, 255, 255, 255, 255, 255, 255, 255, 255],
+ [251, 254, 254, 255, 255, 255, 255, 255, 255, 255, 255],
+ [254, 255, 254, 255, 255, 255, 255, 255, 255, 255, 255],
+ ],
+ [
+ [255, 254, 253, 255, 254, 255, 255, 255, 255, 255, 255],
+ [250, 255, 254, 255, 254, 255, 255, 255, 255, 255, 255],
+ [254, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ ],
+ [
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ ],
+ ],
+ [
+ [
+ [217, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [225, 252, 241, 253, 255, 255, 254, 255, 255, 255, 255],
+ [234, 250, 241, 250, 253, 255, 253, 254, 255, 255, 255],
+ ],
+ [
+ [255, 254, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [223, 254, 254, 255, 255, 255, 255, 255, 255, 255, 255],
+ [238, 253, 254, 254, 255, 255, 255, 255, 255, 255, 255],
+ ],
+ [
+ [255, 248, 254, 255, 255, 255, 255, 255, 255, 255, 255],
+ [249, 254, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ ],
+ [
+ [255, 253, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [247, 254, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ ],
+ [
+ [255, 253, 254, 255, 255, 255, 255, 255, 255, 255, 255],
+ [252, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ ],
+ [
+ [255, 254, 254, 255, 255, 255, 255, 255, 255, 255, 255],
+ [253, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ ],
+ [
+ [255, 254, 253, 255, 255, 255, 255, 255, 255, 255, 255],
+ [250, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [254, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ ],
+ [
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ ],
+ ],
+ [
+ [
+ [186, 251, 250, 255, 255, 255, 255, 255, 255, 255, 255],
+ [234, 251, 244, 254, 255, 255, 255, 255, 255, 255, 255],
+ [251, 251, 243, 253, 254, 255, 254, 255, 255, 255, 255],
+ ],
+ [
+ [255, 253, 254, 255, 255, 255, 255, 255, 255, 255, 255],
+ [236, 253, 254, 255, 255, 255, 255, 255, 255, 255, 255],
+ [251, 253, 253, 254, 254, 255, 255, 255, 255, 255, 255],
+ ],
+ [
+ [255, 254, 254, 255, 255, 255, 255, 255, 255, 255, 255],
+ [254, 254, 254, 255, 255, 255, 255, 255, 255, 255, 255],
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ ],
+ [
+ [255, 254, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [254, 254, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [254, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ ],
+ [
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [254, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ ],
+ [
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ ],
+ [
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ ],
+ [
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ ],
+ ],
+ [
+ [
+ [248, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [250, 254, 252, 254, 255, 255, 255, 255, 255, 255, 255],
+ [248, 254, 249, 253, 255, 255, 255, 255, 255, 255, 255],
+ ],
+ [
+ [255, 253, 253, 255, 255, 255, 255, 255, 255, 255, 255],
+ [246, 253, 253, 255, 255, 255, 255, 255, 255, 255, 255],
+ [252, 254, 251, 254, 254, 255, 255, 255, 255, 255, 255],
+ ],
+ [
+ [255, 254, 252, 255, 255, 255, 255, 255, 255, 255, 255],
+ [248, 254, 253, 255, 255, 255, 255, 255, 255, 255, 255],
+ [253, 255, 254, 254, 255, 255, 255, 255, 255, 255, 255],
+ ],
+ [
+ [255, 251, 254, 255, 255, 255, 255, 255, 255, 255, 255],
+ [245, 251, 254, 255, 255, 255, 255, 255, 255, 255, 255],
+ [253, 253, 254, 255, 255, 255, 255, 255, 255, 255, 255],
+ ],
+ [
+ [255, 251, 253, 255, 255, 255, 255, 255, 255, 255, 255],
+ [252, 253, 254, 255, 255, 255, 255, 255, 255, 255, 255],
+ [255, 254, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ ],
+ [
+ [255, 252, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [249, 255, 254, 255, 255, 255, 255, 255, 255, 255, 255],
+ [255, 255, 254, 255, 255, 255, 255, 255, 255, 255, 255],
+ ],
+ [
+ [255, 255, 253, 255, 255, 255, 255, 255, 255, 255, 255],
+ [250, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ ],
+ [
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [254, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
+ ],
+ ],
+];
+
+// Section 13.5
+// Default Probabilities for tokens
+static COEFF_PROBS: TokenProbTables = [
+ [
+ [
+ [128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128],
+ [128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128],
+ [128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128],
+ ],
+ [
+ [253, 136, 254, 255, 228, 219, 128, 128, 128, 128, 128],
+ [189, 129, 242, 255, 227, 213, 255, 219, 128, 128, 128],
+ [106, 126, 227, 252, 214, 209, 255, 255, 128, 128, 128],
+ ],
+ [
+ [1, 98, 248, 255, 236, 226, 255, 255, 128, 128, 128],
+ [181, 133, 238, 254, 221, 234, 255, 154, 128, 128, 128],
+ [78, 134, 202, 247, 198, 180, 255, 219, 128, 128, 128],
+ ],
+ [
+ [1, 185, 249, 255, 243, 255, 128, 128, 128, 128, 128],
+ [184, 150, 247, 255, 236, 224, 128, 128, 128, 128, 128],
+ [77, 110, 216, 255, 236, 230, 128, 128, 128, 128, 128],
+ ],
+ [
+ [1, 101, 251, 255, 241, 255, 128, 128, 128, 128, 128],
+ [170, 139, 241, 252, 236, 209, 255, 255, 128, 128, 128],
+ [37, 116, 196, 243, 228, 255, 255, 255, 128, 128, 128],
+ ],
+ [
+ [1, 204, 254, 255, 245, 255, 128, 128, 128, 128, 128],
+ [207, 160, 250, 255, 238, 128, 128, 128, 128, 128, 128],
+ [102, 103, 231, 255, 211, 171, 128, 128, 128, 128, 128],
+ ],
+ [
+ [1, 152, 252, 255, 240, 255, 128, 128, 128, 128, 128],
+ [177, 135, 243, 255, 234, 225, 128, 128, 128, 128, 128],
+ [80, 129, 211, 255, 194, 224, 128, 128, 128, 128, 128],
+ ],
+ [
+ [1, 1, 255, 128, 128, 128, 128, 128, 128, 128, 128],
+ [246, 1, 255, 128, 128, 128, 128, 128, 128, 128, 128],
+ [255, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128],
+ ],
+ ],
+ [
+ [
+ [198, 35, 237, 223, 193, 187, 162, 160, 145, 155, 62],
+ [131, 45, 198, 221, 172, 176, 220, 157, 252, 221, 1],
+ [68, 47, 146, 208, 149, 167, 221, 162, 255, 223, 128],
+ ],
+ [
+ [1, 149, 241, 255, 221, 224, 255, 255, 128, 128, 128],
+ [184, 141, 234, 253, 222, 220, 255, 199, 128, 128, 128],
+ [81, 99, 181, 242, 176, 190, 249, 202, 255, 255, 128],
+ ],
+ [
+ [1, 129, 232, 253, 214, 197, 242, 196, 255, 255, 128],
+ [99, 121, 210, 250, 201, 198, 255, 202, 128, 128, 128],
+ [23, 91, 163, 242, 170, 187, 247, 210, 255, 255, 128],
+ ],
+ [
+ [1, 200, 246, 255, 234, 255, 128, 128, 128, 128, 128],
+ [109, 178, 241, 255, 231, 245, 255, 255, 128, 128, 128],
+ [44, 130, 201, 253, 205, 192, 255, 255, 128, 128, 128],
+ ],
+ [
+ [1, 132, 239, 251, 219, 209, 255, 165, 128, 128, 128],
+ [94, 136, 225, 251, 218, 190, 255, 255, 128, 128, 128],
+ [22, 100, 174, 245, 186, 161, 255, 199, 128, 128, 128],
+ ],
+ [
+ [1, 182, 249, 255, 232, 235, 128, 128, 128, 128, 128],
+ [124, 143, 241, 255, 227, 234, 128, 128, 128, 128, 128],
+ [35, 77, 181, 251, 193, 211, 255, 205, 128, 128, 128],
+ ],
+ [
+ [1, 157, 247, 255, 236, 231, 255, 255, 128, 128, 128],
+ [121, 141, 235, 255, 225, 227, 255, 255, 128, 128, 128],
+ [45, 99, 188, 251, 195, 217, 255, 224, 128, 128, 128],
+ ],
+ [
+ [1, 1, 251, 255, 213, 255, 128, 128, 128, 128, 128],
+ [203, 1, 248, 255, 255, 128, 128, 128, 128, 128, 128],
+ [137, 1, 177, 255, 224, 255, 128, 128, 128, 128, 128],
+ ],
+ ],
+ [
+ [
+ [253, 9, 248, 251, 207, 208, 255, 192, 128, 128, 128],
+ [175, 13, 224, 243, 193, 185, 249, 198, 255, 255, 128],
+ [73, 17, 171, 221, 161, 179, 236, 167, 255, 234, 128],
+ ],
+ [
+ [1, 95, 247, 253, 212, 183, 255, 255, 128, 128, 128],
+ [239, 90, 244, 250, 211, 209, 255, 255, 128, 128, 128],
+ [155, 77, 195, 248, 188, 195, 255, 255, 128, 128, 128],
+ ],
+ [
+ [1, 24, 239, 251, 218, 219, 255, 205, 128, 128, 128],
+ [201, 51, 219, 255, 196, 186, 128, 128, 128, 128, 128],
+ [69, 46, 190, 239, 201, 218, 255, 228, 128, 128, 128],
+ ],
+ [
+ [1, 191, 251, 255, 255, 128, 128, 128, 128, 128, 128],
+ [223, 165, 249, 255, 213, 255, 128, 128, 128, 128, 128],
+ [141, 124, 248, 255, 255, 128, 128, 128, 128, 128, 128],
+ ],
+ [
+ [1, 16, 248, 255, 255, 128, 128, 128, 128, 128, 128],
+ [190, 36, 230, 255, 236, 255, 128, 128, 128, 128, 128],
+ [149, 1, 255, 128, 128, 128, 128, 128, 128, 128, 128],
+ ],
+ [
+ [1, 226, 255, 128, 128, 128, 128, 128, 128, 128, 128],
+ [247, 192, 255, 128, 128, 128, 128, 128, 128, 128, 128],
+ [240, 128, 255, 128, 128, 128, 128, 128, 128, 128, 128],
+ ],
+ [
+ [1, 134, 252, 255, 255, 128, 128, 128, 128, 128, 128],
+ [213, 62, 250, 255, 255, 128, 128, 128, 128, 128, 128],
+ [55, 93, 255, 128, 128, 128, 128, 128, 128, 128, 128],
+ ],
+ [
+ [128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128],
+ [128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128],
+ [128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128],
+ ],
+ ],
+ [
+ [
+ [202, 24, 213, 235, 186, 191, 220, 160, 240, 175, 255],
+ [126, 38, 182, 232, 169, 184, 228, 174, 255, 187, 128],
+ [61, 46, 138, 219, 151, 178, 240, 170, 255, 216, 128],
+ ],
+ [
+ [1, 112, 230, 250, 199, 191, 247, 159, 255, 255, 128],
+ [166, 109, 228, 252, 211, 215, 255, 174, 128, 128, 128],
+ [39, 77, 162, 232, 172, 180, 245, 178, 255, 255, 128],
+ ],
+ [
+ [1, 52, 220, 246, 198, 199, 249, 220, 255, 255, 128],
+ [124, 74, 191, 243, 183, 193, 250, 221, 255, 255, 128],
+ [24, 71, 130, 219, 154, 170, 243, 182, 255, 255, 128],
+ ],
+ [
+ [1, 182, 225, 249, 219, 240, 255, 224, 128, 128, 128],
+ [149, 150, 226, 252, 216, 205, 255, 171, 128, 128, 128],
+ [28, 108, 170, 242, 183, 194, 254, 223, 255, 255, 128],
+ ],
+ [
+ [1, 81, 230, 252, 204, 203, 255, 192, 128, 128, 128],
+ [123, 102, 209, 247, 188, 196, 255, 233, 128, 128, 128],
+ [20, 95, 153, 243, 164, 173, 255, 203, 128, 128, 128],
+ ],
+ [
+ [1, 222, 248, 255, 216, 213, 128, 128, 128, 128, 128],
+ [168, 175, 246, 252, 235, 205, 255, 255, 128, 128, 128],
+ [47, 116, 215, 255, 211, 212, 255, 255, 128, 128, 128],
+ ],
+ [
+ [1, 121, 236, 253, 212, 214, 255, 255, 128, 128, 128],
+ [141, 84, 213, 252, 201, 202, 255, 219, 128, 128, 128],
+ [42, 80, 160, 240, 162, 185, 255, 205, 128, 128, 128],
+ ],
+ [
+ [1, 1, 255, 128, 128, 128, 128, 128, 128, 128, 128],
+ [244, 1, 255, 128, 128, 128, 128, 128, 128, 128, 128],
+ [238, 1, 255, 128, 128, 128, 128, 128, 128, 128, 128],
+ ],
+ ],
+];
+
+// DCT Tokens
+const DCT_0: i8 = 0;
+const DCT_1: i8 = 1;
+const DCT_2: i8 = 2;
+const DCT_3: i8 = 3;
+const DCT_4: i8 = 4;
+const DCT_CAT1: i8 = 5;
+const DCT_CAT2: i8 = 6;
+const DCT_CAT3: i8 = 7;
+const DCT_CAT4: i8 = 8;
+const DCT_CAT5: i8 = 9;
+const DCT_CAT6: i8 = 10;
+const DCT_EOB: i8 = 11;
+
+static DCT_TOKEN_TREE: [i8; 22] = [
+ -DCT_EOB, 2, -DCT_0, 4, -DCT_1, 6, 8, 12, -DCT_2, 10, -DCT_3, -DCT_4, 14, 16, -DCT_CAT1,
+ -DCT_CAT2, 18, 20, -DCT_CAT3, -DCT_CAT4, -DCT_CAT5, -DCT_CAT6,
+];
+
+static PROB_DCT_CAT: [[Prob; 12]; 6] = [
+ [159, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
+ [165, 145, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
+ [173, 148, 140, 0, 0, 0, 0, 0, 0, 0, 0, 0],
+ [176, 155, 140, 135, 0, 0, 0, 0, 0, 0, 0, 0],
+ [180, 157, 141, 134, 130, 0, 0, 0, 0, 0, 0, 0],
+ [254, 254, 243, 230, 196, 177, 153, 140, 133, 130, 129, 0],
+];
+
+static DCT_CAT_BASE: [u8; 6] = [5, 7, 11, 19, 35, 67];
+static COEFF_BANDS: [u8; 16] = [0, 1, 2, 3, 6, 4, 5, 6, 6, 6, 6, 6, 6, 6, 6, 7];
+
+#[rustfmt::skip]
+static DC_QUANT: [i16; 128] = [
+ 4, 5, 6, 7, 8, 9, 10, 10,
+ 11, 12, 13, 14, 15, 16, 17, 17,
+ 18, 19, 20, 20, 21, 21, 22, 22,
+ 23, 23, 24, 25, 25, 26, 27, 28,
+ 29, 30, 31, 32, 33, 34, 35, 36,
+ 37, 37, 38, 39, 40, 41, 42, 43,
+ 44, 45, 46, 46, 47, 48, 49, 50,
+ 51, 52, 53, 54, 55, 56, 57, 58,
+ 59, 60, 61, 62, 63, 64, 65, 66,
+ 67, 68, 69, 70, 71, 72, 73, 74,
+ 75, 76, 76, 77, 78, 79, 80, 81,
+ 82, 83, 84, 85, 86, 87, 88, 89,
+ 91, 93, 95, 96, 98, 100, 101, 102,
+ 104, 106, 108, 110, 112, 114, 116, 118,
+ 122, 124, 126, 128, 130, 132, 134, 136,
+ 138, 140, 143, 145, 148, 151, 154, 157,
+];
+
+#[rustfmt::skip]
+static AC_QUANT: [i16; 128] = [
+ 4, 5, 6, 7, 8, 9, 10, 11,
+ 12, 13, 14, 15, 16, 17, 18, 19,
+ 20, 21, 22, 23, 24, 25, 26, 27,
+ 28, 29, 30, 31, 32, 33, 34, 35,
+ 36, 37, 38, 39, 40, 41, 42, 43,
+ 44, 45, 46, 47, 48, 49, 50, 51,
+ 52, 53, 54, 55, 56, 57, 58, 60,
+ 62, 64, 66, 68, 70, 72, 74, 76,
+ 78, 80, 82, 84, 86, 88, 90, 92,
+ 94, 96, 98, 100, 102, 104, 106, 108,
+ 110, 112, 114, 116, 119, 122, 125, 128,
+ 131, 134, 137, 140, 143, 146, 149, 152,
+ 155, 158, 161, 164, 167, 170, 173, 177,
+ 181, 185, 189, 193, 197, 201, 205, 209,
+ 213, 217, 221, 225, 229, 234, 239, 245,
+ 249, 254, 259, 264, 269, 274, 279, 284,
+];
+
+static ZIGZAG: [u8; 16] = [0, 1, 4, 8, 5, 2, 3, 6, 9, 12, 13, 10, 7, 11, 14, 15];
+
+/// All errors that can occur when attempting to parse a VP8 codec inside WebP
+#[derive(Debug, Clone, Copy)]
+enum DecoderError {
+ /// VP8's `[0x9D, 0x01, 0x2A]` magic not found or invalid
+ Vp8MagicInvalid([u8; 3]),
+
+ /// Decoder initialisation wasn't provided with enough data
+ NotEnoughInitData,
+
+ /// At time of writing, only the YUV colour-space encoded as `0` is specified
+ ColorSpaceInvalid(u8),
+ /// LUMA prediction mode was not recognised
+ LumaPredictionModeInvalid(i8),
+ /// Intra-prediction mode was not recognised
+ IntraPredictionModeInvalid(i8),
+ /// Chroma prediction mode was not recognised
+ ChromaPredictionModeInvalid(i8),
+}
+
+impl fmt::Display for DecoderError {
+ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+ match self {
+ DecoderError::Vp8MagicInvalid(tag) => f.write_fmt(format_args!(
+ "Invalid VP8 magic: [{:#04X?}, {:#04X?}, {:#04X?}]",
+ tag[0], tag[1], tag[2]
+ )),
+
+ DecoderError::NotEnoughInitData => {
+ f.write_str("Expected at least 2 bytes of VP8 decoder initialization data")
+ }
+
+ DecoderError::ColorSpaceInvalid(cs) => {
+ f.write_fmt(format_args!("Invalid non-YUV VP8 color space {}", cs))
+ }
+ DecoderError::LumaPredictionModeInvalid(pm) => {
+ f.write_fmt(format_args!("Invalid VP8 LUMA prediction mode {}", pm))
+ }
+ DecoderError::IntraPredictionModeInvalid(i) => {
+ f.write_fmt(format_args!("Invalid VP8 intra-prediction mode {}", i))
+ }
+ DecoderError::ChromaPredictionModeInvalid(c) => {
+ f.write_fmt(format_args!("Invalid VP8 chroma prediction mode {}", c))
+ }
+ }
+ }
+}
+
+impl From<DecoderError> for ImageError {
+ fn from(e: DecoderError) -> ImageError {
+ ImageError::Decoding(DecodingError::new(ImageFormat::WebP.into(), e))
+ }
+}
+
+impl error::Error for DecoderError {}
+
+struct BoolReader {
+ buf: Vec<u8>,
+ index: usize,
+
+ range: u32,
+ value: u32,
+ bit_count: u8,
+}
+
+impl BoolReader {
+ pub(crate) fn new() -> BoolReader {
+ BoolReader {
+ buf: Vec::new(),
+ range: 0,
+ value: 0,
+ bit_count: 0,
+ index: 0,
+ }
+ }
+
+ pub(crate) fn init(&mut self, buf: Vec<u8>) -> ImageResult<()> {
+ if buf.len() < 2 {
+ return Err(DecoderError::NotEnoughInitData.into());
+ }
+
+ self.buf = buf;
+ // Direct access safe, since length has just been validated.
+ self.value = (u32::from(self.buf[0]) << 8) | u32::from(self.buf[1]);
+ self.index = 2;
+ self.range = 255;
+ self.bit_count = 0;
+
+ Ok(())
+ }
+
+ pub(crate) fn read_bool(&mut self, probability: u8) -> bool {
+ let split = 1 + (((self.range - 1) * u32::from(probability)) >> 8);
+ let bigsplit = split << 8;
+
+ let retval = if self.value >= bigsplit {
+ self.range -= split;
+ self.value -= bigsplit;
+ true
+ } else {
+ self.range = split;
+ false
+ };
+
+ while self.range < 128 {
+ self.value <<= 1;
+ self.range <<= 1;
+ self.bit_count += 1;
+
+ if self.bit_count == 8 {
+ self.bit_count = 0;
+
+ // If no more bits are available, just don't do anything.
+ // This strategy is suggested in the reference implementation of RFC6386 (p.135)
+ if self.index < self.buf.len() {
+ self.value |= u32::from(self.buf[self.index]);
+ self.index += 1;
+ }
+ }
+ }
+
+ retval
+ }
+
+ pub(crate) fn read_literal(&mut self, n: u8) -> u8 {
+ let mut v = 0u8;
+ let mut n = n;
+
+ while n != 0 {
+ v = (v << 1) + self.read_bool(128u8) as u8;
+ n -= 1;
+ }
+
+ v
+ }
+
+ pub(crate) fn read_magnitude_and_sign(&mut self, n: u8) -> i32 {
+ let magnitude = self.read_literal(n);
+ let sign = self.read_literal(1);
+
+ if sign == 1 {
+ -i32::from(magnitude)
+ } else {
+ i32::from(magnitude)
+ }
+ }
+
+ pub(crate) fn read_with_tree(&mut self, tree: &[i8], probs: &[Prob], start: isize) -> i8 {
+ let mut index = start;
+
+ loop {
+ let a = self.read_bool(probs[index as usize >> 1]);
+ let b = index + a as isize;
+ index = tree[b as usize] as isize;
+
+ if index <= 0 {
+ break;
+ }
+ }
+
+ -index as i8
+ }
+
+ pub(crate) fn read_flag(&mut self) -> bool {
+ 0 != self.read_literal(1)
+ }
+}
+
+#[derive(Default, Clone, Copy)]
+struct MacroBlock {
+ bpred: [IntraMode; 16],
+ complexity: [u8; 9],
+ luma_mode: LumaMode,
+ chroma_mode: ChromaMode,
+ segmentid: u8,
+ coeffs_skipped: bool,
+}
+
+/// A Representation of the last decoded video frame
+#[derive(Default, Debug, Clone)]
+pub struct Frame {
+ /// The width of the luma plane
+ pub width: u16,
+
+ /// The height of the luma plane
+ pub height: u16,
+
+ /// The luma plane of the frame
+ pub ybuf: Vec<u8>,
+
+ /// The blue plane of the frame
+ pub ubuf: Vec<u8>,
+
+ /// The red plane of the frame
+ pub vbuf: Vec<u8>,
+
+ /// Indicates whether this frame is a keyframe
+ pub keyframe: bool,
+
+ version: u8,
+
+ /// Indicates whether this frame is intended for display
+ pub for_display: bool,
+
+ // Section 9.2
+ /// The pixel type of the frame as defined by Section 9.2
+ /// of the VP8 Specification
+ pub pixel_type: u8,
+
+ // Section 9.4 and 15
+ filter_type: bool, //if true uses simple filter // if false uses normal filter
+ filter_level: u8,
+ sharpness_level: u8,
+}
+
+impl Frame {
+ /// Chroma plane is half the size of the Luma plane
+ fn chroma_width(&self) -> u16 {
+ (self.width + 1) / 2
+ }
+
+ fn chroma_height(&self) -> u16 {
+ (self.height + 1) / 2
+ }
+
+ /// Fills an rgb buffer with the image
+ pub(crate) fn fill_rgb(&self, buf: &mut [u8]) {
+ for (index, rgb_chunk) in (0..self.ybuf.len()).zip(buf.chunks_exact_mut(3)) {
+ let y = index / self.width as usize;
+ let x = index % self.width as usize;
+ let chroma_index = self.chroma_width() as usize * (y / 2) + x / 2;
+
+ Frame::fill_single(
+ self.ybuf[index],
+ self.ubuf[chroma_index],
+ self.vbuf[chroma_index],
+ rgb_chunk,
+ );
+ }
+ }
+
+ /// Fills an rgba buffer by skipping the alpha values
+ pub(crate) fn fill_rgba(&self, buf: &mut [u8]) {
+ for (index, rgba_chunk) in (0..self.ybuf.len()).zip(buf.chunks_exact_mut(4)) {
+ let y = index / self.width as usize;
+ let x = index % self.width as usize;
+ let chroma_index = self.chroma_width() as usize * (y / 2) + x / 2;
+
+ Frame::fill_single(
+ self.ybuf[index],
+ self.ubuf[chroma_index],
+ self.vbuf[chroma_index],
+ rgba_chunk,
+ );
+ }
+ }
+
+ /// Conversion values from https://docs.microsoft.com/en-us/windows/win32/medfound/recommended-8-bit-yuv-formats-for-video-rendering#converting-8-bit-yuv-to-rgb888
+ fn fill_single(y: u8, u: u8, v: u8, rgb: &mut [u8]) {
+ let c: i32 = i32::from(y) - 16;
+ let d: i32 = i32::from(u) - 128;
+ let e: i32 = i32::from(v) - 128;
+
+ let r: u8 = clamp((298 * c + 409 * e + 128) >> 8, 0, 255)
+ .try_into()
+ .unwrap();
+ let g: u8 = clamp((298 * c - 100 * d - 208 * e + 128) >> 8, 0, 255)
+ .try_into()
+ .unwrap();
+ let b: u8 = clamp((298 * c + 516 * d + 128) >> 8, 0, 255)
+ .try_into()
+ .unwrap();
+
+ rgb[0] = r;
+ rgb[1] = g;
+ rgb[2] = b;
+ }
+
+ /// Gets the buffer size
+ pub fn get_buf_size(&self) -> usize {
+ self.ybuf.len() * 3
+ }
+}
+
+#[derive(Clone, Copy, Default)]
+struct Segment {
+ ydc: i16,
+ yac: i16,
+
+ y2dc: i16,
+ y2ac: i16,
+
+ uvdc: i16,
+ uvac: i16,
+
+ delta_values: bool,
+
+ quantizer_level: i8,
+ loopfilter_level: i8,
+}
+
+/// VP8 Decoder
+///
+/// Only decodes keyframes
+pub struct Vp8Decoder<R> {
+ r: R,
+ b: BoolReader,
+
+ mbwidth: u16,
+ mbheight: u16,
+ macroblocks: Vec<MacroBlock>,
+
+ frame: Frame,
+
+ segments_enabled: bool,
+ segments_update_map: bool,
+ segment: [Segment; MAX_SEGMENTS],
+
+ ref_delta: [i32; 4],
+ mode_delta: [i32; 4],
+
+ partitions: [BoolReader; 8],
+ num_partitions: u8,
+
+ segment_tree_probs: [Prob; 3],
+ token_probs: Box<TokenProbTables>,
+
+ // Section 9.10
+ prob_intra: Prob,
+
+ // Section 9.11
+ prob_skip_false: Option<Prob>,
+
+ top: Vec<MacroBlock>,
+ left: MacroBlock,
+
+ top_border: Vec<u8>,
+ left_border: Vec<u8>,
+}
+
+impl<R: Read> Vp8Decoder<R> {
+ /// Create a new decoder.
+ /// The reader must present a raw vp8 bitstream to the decoder
+ pub fn new(r: R) -> Vp8Decoder<R> {
+ let f = Frame::default();
+ let s = Segment::default();
+ let m = MacroBlock::default();
+
+ Vp8Decoder {
+ r,
+ b: BoolReader::new(),
+
+ mbwidth: 0,
+ mbheight: 0,
+ macroblocks: Vec::new(),
+
+ frame: f,
+ segments_enabled: false,
+ segments_update_map: false,
+ segment: [s; MAX_SEGMENTS],
+
+ ref_delta: [0; 4],
+ mode_delta: [0; 4],
+
+ partitions: [
+ BoolReader::new(),
+ BoolReader::new(),
+ BoolReader::new(),
+ BoolReader::new(),
+ BoolReader::new(),
+ BoolReader::new(),
+ BoolReader::new(),
+ BoolReader::new(),
+ ],
+
+ num_partitions: 1,
+
+ segment_tree_probs: [255u8; 3],
+ token_probs: Box::new(COEFF_PROBS),
+
+ // Section 9.10
+ prob_intra: 0u8,
+
+ // Section 9.11
+ prob_skip_false: None,
+
+ top: Vec::new(),
+ left: m,
+
+ top_border: Vec::new(),
+ left_border: Vec::new(),
+ }
+ }
+
+ fn update_token_probabilities(&mut self) {
+ for (i, is) in COEFF_UPDATE_PROBS.iter().enumerate() {
+ for (j, js) in is.iter().enumerate() {
+ for (k, ks) in js.iter().enumerate() {
+ for (t, prob) in ks.iter().enumerate().take(NUM_DCT_TOKENS - 1) {
+ if self.b.read_bool(*prob) {
+ let v = self.b.read_literal(8);
+ self.token_probs[i][j][k][t] = v;
+ }
+ }
+ }
+ }
+ }
+ }
+
+ fn init_partitions(&mut self, n: usize) -> ImageResult<()> {
+ if n > 1 {
+ let mut sizes = vec![0; 3 * n - 3];
+ self.r.read_exact(sizes.as_mut_slice())?;
+
+ for (i, s) in sizes.chunks(3).enumerate() {
+ let size = { s }
+ .read_u24::<LittleEndian>()
+ .expect("Reading from &[u8] can't fail and the chunk is complete");
+
+ let mut buf = vec![0; size as usize];
+ self.r.read_exact(buf.as_mut_slice())?;
+
+ self.partitions[i].init(buf)?;
+ }
+ }
+
+ let mut buf = Vec::new();
+ self.r.read_to_end(&mut buf)?;
+ self.partitions[n - 1].init(buf)?;
+
+ Ok(())
+ }
+
+ fn read_quantization_indices(&mut self) {
+ fn dc_quant(index: i32) -> i16 {
+ DC_QUANT[clamp(index, 0, 127) as usize]
+ }
+
+ fn ac_quant(index: i32) -> i16 {
+ AC_QUANT[clamp(index, 0, 127) as usize]
+ }
+
+ let yac_abs = self.b.read_literal(7);
+ let ydc_delta = if self.b.read_flag() {
+ self.b.read_magnitude_and_sign(4)
+ } else {
+ 0
+ };
+
+ let y2dc_delta = if self.b.read_flag() {
+ self.b.read_magnitude_and_sign(4)
+ } else {
+ 0
+ };
+
+ let y2ac_delta = if self.b.read_flag() {
+ self.b.read_magnitude_and_sign(4)
+ } else {
+ 0
+ };
+
+ let uvdc_delta = if self.b.read_flag() {
+ self.b.read_magnitude_and_sign(4)
+ } else {
+ 0
+ };
+
+ let uvac_delta = if self.b.read_flag() {
+ self.b.read_magnitude_and_sign(4)
+ } else {
+ 0
+ };
+
+ let n = if self.segments_enabled {
+ MAX_SEGMENTS
+ } else {
+ 1
+ };
+ for i in 0usize..n {
+ let base = i32::from(if !self.segment[i].delta_values {
+ i16::from(self.segment[i].quantizer_level)
+ } else {
+ i16::from(self.segment[i].quantizer_level) + i16::from(yac_abs)
+ });
+
+ self.segment[i].ydc = dc_quant(base + ydc_delta);
+ self.segment[i].yac = ac_quant(base);
+
+ self.segment[i].y2dc = dc_quant(base + y2dc_delta) * 2;
+ // The intermediate result (max`284*155`) can be larger than the `i16` range.
+ self.segment[i].y2ac = (i32::from(ac_quant(base + y2ac_delta)) * 155 / 100) as i16;
+
+ self.segment[i].uvdc = dc_quant(base + uvdc_delta);
+ self.segment[i].uvac = ac_quant(base + uvac_delta);
+
+ if self.segment[i].y2ac < 8 {
+ self.segment[i].y2ac = 8;
+ }
+
+ if self.segment[i].uvdc > 132 {
+ self.segment[i].uvdc = 132;
+ }
+ }
+ }
+
+ fn read_loop_filter_adjustments(&mut self) {
+ if self.b.read_flag() {
+ for i in 0usize..4 {
+ let ref_frame_delta_update_flag = self.b.read_flag();
+
+ self.ref_delta[i] = if ref_frame_delta_update_flag {
+ self.b.read_magnitude_and_sign(6)
+ } else {
+ 0i32
+ };
+ }
+
+ for i in 0usize..4 {
+ let mb_mode_delta_update_flag = self.b.read_flag();
+
+ self.mode_delta[i] = if mb_mode_delta_update_flag {
+ self.b.read_magnitude_and_sign(6)
+ } else {
+ 0i32
+ };
+ }
+ }
+ }
+
+ fn read_segment_updates(&mut self) {
+ // Section 9.3
+ self.segments_update_map = self.b.read_flag();
+ let update_segment_feature_data = self.b.read_flag();
+
+ if update_segment_feature_data {
+ let segment_feature_mode = self.b.read_flag();
+
+ for i in 0usize..MAX_SEGMENTS {
+ self.segment[i].delta_values = !segment_feature_mode;
+ }
+
+ for i in 0usize..MAX_SEGMENTS {
+ let update = self.b.read_flag();
+
+ self.segment[i].quantizer_level = if update {
+ self.b.read_magnitude_and_sign(7)
+ } else {
+ 0i32
+ } as i8;
+ }
+
+ for i in 0usize..MAX_SEGMENTS {
+ let update = self.b.read_flag();
+
+ self.segment[i].loopfilter_level = if update {
+ self.b.read_magnitude_and_sign(6)
+ } else {
+ 0i32
+ } as i8;
+ }
+ }
+
+ if self.segments_update_map {
+ for i in 0usize..3 {
+ let update = self.b.read_flag();
+
+ self.segment_tree_probs[i] = if update { self.b.read_literal(8) } else { 255 };
+ }
+ }
+ }
+
+ fn read_frame_header(&mut self) -> ImageResult<()> {
+ let tag = self.r.read_u24::<LittleEndian>()?;
+
+ self.frame.keyframe = tag & 1 == 0;
+ self.frame.version = ((tag >> 1) & 7) as u8;
+ self.frame.for_display = (tag >> 4) & 1 != 0;
+
+ let first_partition_size = tag >> 5;
+
+ if self.frame.keyframe {
+ let mut tag = [0u8; 3];
+ self.r.read_exact(&mut tag)?;
+
+ if tag != [0x9d, 0x01, 0x2a] {
+ return Err(DecoderError::Vp8MagicInvalid(tag).into());
+ }
+
+ let w = self.r.read_u16::<LittleEndian>()?;
+ let h = self.r.read_u16::<LittleEndian>()?;
+
+ self.frame.width = w & 0x3FFF;
+ self.frame.height = h & 0x3FFF;
+
+ self.top = init_top_macroblocks(self.frame.width as usize);
+ // Almost always the first macro block, except when non exists (i.e. `width == 0`)
+ self.left = self.top.get(0).cloned().unwrap_or_default();
+
+ self.mbwidth = (self.frame.width + 15) / 16;
+ self.mbheight = (self.frame.height + 15) / 16;
+
+ self.frame.ybuf = vec![0u8; self.frame.width as usize * self.frame.height as usize];
+ self.frame.ubuf =
+ vec![0u8; self.frame.chroma_width() as usize * self.frame.chroma_height() as usize];
+ self.frame.vbuf =
+ vec![0u8; self.frame.chroma_width() as usize * self.frame.chroma_height() as usize];
+
+ self.top_border = vec![127u8; self.frame.width as usize + 4 + 16];
+ self.left_border = vec![129u8; 1 + 16];
+ }
+
+ let mut buf = vec![0; first_partition_size as usize];
+ self.r.read_exact(&mut buf)?;
+
+ // initialise binary decoder
+ self.b.init(buf)?;
+
+ if self.frame.keyframe {
+ let color_space = self.b.read_literal(1);
+ self.frame.pixel_type = self.b.read_literal(1);
+
+ if color_space != 0 {
+ return Err(DecoderError::ColorSpaceInvalid(color_space).into());
+ }
+ }
+
+ self.segments_enabled = self.b.read_flag();
+ if self.segments_enabled {
+ self.read_segment_updates();
+ }
+
+ self.frame.filter_type = self.b.read_flag();
+ self.frame.filter_level = self.b.read_literal(6);
+ self.frame.sharpness_level = self.b.read_literal(3);
+
+ let lf_adjust_enable = self.b.read_flag();
+ if lf_adjust_enable {
+ self.read_loop_filter_adjustments();
+ }
+
+ self.num_partitions = (1usize << self.b.read_literal(2) as usize) as u8;
+ let num_partitions = self.num_partitions as usize;
+ self.init_partitions(num_partitions)?;
+
+ self.read_quantization_indices();
+
+ if !self.frame.keyframe {
+ // 9.7 refresh golden frame and altref frame
+ // FIXME: support this?
+ return Err(ImageError::Unsupported(
+ UnsupportedError::from_format_and_kind(
+ ImageFormat::WebP.into(),
+ UnsupportedErrorKind::GenericFeature("Non-keyframe frames".to_owned()),
+ ),
+ ));
+ } else {
+ // Refresh entropy probs ?????
+ let _ = self.b.read_literal(1);
+ }
+
+ self.update_token_probabilities();
+
+ let mb_no_skip_coeff = self.b.read_literal(1);
+ self.prob_skip_false = if mb_no_skip_coeff == 1 {
+ Some(self.b.read_literal(8))
+ } else {
+ None
+ };
+
+ if !self.frame.keyframe {
+ // 9.10 remaining frame data
+ self.prob_intra = 0;
+
+ // FIXME: support this?
+ return Err(ImageError::Unsupported(
+ UnsupportedError::from_format_and_kind(
+ ImageFormat::WebP.into(),
+ UnsupportedErrorKind::GenericFeature("Non-keyframe frames".to_owned()),
+ ),
+ ));
+ } else {
+ // Reset motion vectors
+ }
+
+ Ok(())
+ }
+
+ fn read_macroblock_header(&mut self, mbx: usize) -> ImageResult<MacroBlock> {
+ let mut mb = MacroBlock::default();
+
+ if self.segments_enabled && self.segments_update_map {
+ mb.segmentid = self
+ .b
+ .read_with_tree(&SEGMENT_ID_TREE, &self.segment_tree_probs, 0)
+ as u8;
+ };
+
+ mb.coeffs_skipped = if self.prob_skip_false.is_some() {
+ self.b.read_bool(*self.prob_skip_false.as_ref().unwrap())
+ } else {
+ false
+ };
+
+ let inter_predicted = if !self.frame.keyframe {
+ self.b.read_bool(self.prob_intra)
+ } else {
+ false
+ };
+
+ if inter_predicted {
+ return Err(ImageError::Unsupported(
+ UnsupportedError::from_format_and_kind(
+ ImageFormat::WebP.into(),
+ UnsupportedErrorKind::GenericFeature("VP8 inter-prediction".to_owned()),
+ ),
+ ));
+ }
+
+ if self.frame.keyframe {
+ // intra prediction
+ let luma = self
+ .b
+ .read_with_tree(&KEYFRAME_YMODE_TREE, &KEYFRAME_YMODE_PROBS, 0);
+ mb.luma_mode =
+ LumaMode::from_i8(luma).ok_or(DecoderError::LumaPredictionModeInvalid(luma))?;
+
+ match mb.luma_mode.into_intra() {
+ // `LumaMode::B` - This is predicted individually
+ None => {
+ for y in 0usize..4 {
+ for x in 0usize..4 {
+ let top = self.top[mbx].bpred[12 + x];
+ let left = self.left.bpred[y];
+ let intra = self.b.read_with_tree(
+ &KEYFRAME_BPRED_MODE_TREE,
+ &KEYFRAME_BPRED_MODE_PROBS[top as usize][left as usize],
+ 0,
+ );
+ let bmode = IntraMode::from_i8(intra)
+ .ok_or(DecoderError::IntraPredictionModeInvalid(intra))?;
+ mb.bpred[x + y * 4] = bmode;
+
+ self.top[mbx].bpred[12 + x] = bmode;
+ self.left.bpred[y] = bmode;
+ }
+ }
+ }
+ Some(mode) => {
+ for i in 0usize..4 {
+ mb.bpred[12 + i] = mode;
+ self.left.bpred[i] = mode;
+ }
+ }
+ }
+
+ let chroma = self
+ .b
+ .read_with_tree(&KEYFRAME_UV_MODE_TREE, &KEYFRAME_UV_MODE_PROBS, 0);
+ mb.chroma_mode = ChromaMode::from_i8(chroma)
+ .ok_or(DecoderError::ChromaPredictionModeInvalid(chroma))?;
+ }
+
+ self.top[mbx].chroma_mode = mb.chroma_mode;
+ self.top[mbx].luma_mode = mb.luma_mode;
+ self.top[mbx].bpred = mb.bpred;
+
+ Ok(mb)
+ }
+
+ fn intra_predict_luma(&mut self, mbx: usize, mby: usize, mb: &MacroBlock, resdata: &[i32]) {
+ let stride = 1usize + 16 + 4;
+ let w = self.frame.width as usize;
+ let mw = self.mbwidth as usize;
+ let mut ws = create_border_luma(mbx, mby, mw, &self.top_border, &self.left_border);
+
+ match mb.luma_mode {
+ LumaMode::V => predict_vpred(&mut ws, 16, 1, 1, stride),
+ LumaMode::H => predict_hpred(&mut ws, 16, 1, 1, stride),
+ LumaMode::TM => predict_tmpred(&mut ws, 16, 1, 1, stride),
+ LumaMode::DC => predict_dcpred(&mut ws, 16, stride, mby != 0, mbx != 0),
+ LumaMode::B => predict_4x4(&mut ws, stride, &mb.bpred, resdata),
+ }
+
+ if mb.luma_mode != LumaMode::B {
+ for y in 0usize..4 {
+ for x in 0usize..4 {
+ let i = x + y * 4;
+ // Create a reference to a [i32; 16] array for add_residue (slices of size 16 do not work).
+ let rb: &[i32; 16] = resdata[i * 16..][..16].try_into().unwrap();
+ let y0 = 1 + y * 4;
+ let x0 = 1 + x * 4;
+
+ add_residue(&mut ws, rb, y0, x0, stride);
+ }
+ }
+ }
+
+ self.left_border[0] = ws[16];
+
+ for i in 0usize..16 {
+ self.top_border[mbx * 16 + i] = ws[16 * stride + 1 + i];
+ self.left_border[i + 1] = ws[(i + 1) * stride + 16];
+ }
+
+ // Length is the remainder to the border, but maximally the current chunk.
+ let ylength = cmp::min(self.frame.height as usize - mby * 16, 16);
+ let xlength = cmp::min(self.frame.width as usize - mbx * 16, 16);
+
+ for y in 0usize..ylength {
+ for x in 0usize..xlength {
+ self.frame.ybuf[(mby * 16 + y) * w + mbx * 16 + x] = ws[(1 + y) * stride + 1 + x];
+ }
+ }
+ }
+
+ fn intra_predict_chroma(&mut self, mbx: usize, mby: usize, mb: &MacroBlock, resdata: &[i32]) {
+ let stride = 1usize + 8;
+
+ let w = self.frame.chroma_width() as usize;
+
+ //8x8 with left top border of 1
+ let mut uws = [0u8; (8 + 1) * (8 + 1)];
+ let mut vws = [0u8; (8 + 1) * (8 + 1)];
+
+ let ylength = cmp::min(self.frame.chroma_height() as usize - mby * 8, 8);
+ let xlength = cmp::min(self.frame.chroma_width() as usize - mbx * 8, 8);
+
+ //left border
+ for y in 0usize..8 {
+ let (uy, vy) = if mbx == 0 || y >= ylength {
+ (129, 129)
+ } else {
+ let index = (mby * 8 + y) * w + ((mbx - 1) * 8 + 7);
+ (self.frame.ubuf[index], self.frame.vbuf[index])
+ };
+
+ uws[(y + 1) * stride] = uy;
+ vws[(y + 1) * stride] = vy;
+ }
+ //top border
+ for x in 0usize..8 {
+ let (ux, vx) = if mby == 0 || x >= xlength {
+ (127, 127)
+ } else {
+ let index = ((mby - 1) * 8 + 7) * w + (mbx * 8 + x);
+ (self.frame.ubuf[index], self.frame.vbuf[index])
+ };
+
+ uws[x + 1] = ux;
+ vws[x + 1] = vx;
+ }
+
+ //top left point
+ let (u1, v1) = if mby == 0 {
+ (127, 127)
+ } else if mbx == 0 {
+ (129, 129)
+ } else {
+ let index = ((mby - 1) * 8 + 7) * w + (mbx - 1) * 8 + 7;
+ if index >= self.frame.ubuf.len() {
+ (127, 127)
+ } else {
+ (self.frame.ubuf[index], self.frame.vbuf[index])
+ }
+ };
+
+ uws[0] = u1;
+ vws[0] = v1;
+
+ match mb.chroma_mode {
+ ChromaMode::DC => {
+ predict_dcpred(&mut uws, 8, stride, mby != 0, mbx != 0);
+ predict_dcpred(&mut vws, 8, stride, mby != 0, mbx != 0);
+ }
+ ChromaMode::V => {
+ predict_vpred(&mut uws, 8, 1, 1, stride);
+ predict_vpred(&mut vws, 8, 1, 1, stride);
+ }
+ ChromaMode::H => {
+ predict_hpred(&mut uws, 8, 1, 1, stride);
+ predict_hpred(&mut vws, 8, 1, 1, stride);
+ }
+ ChromaMode::TM => {
+ predict_tmpred(&mut uws, 8, 1, 1, stride);
+ predict_tmpred(&mut vws, 8, 1, 1, stride);
+ }
+ }
+
+ for y in 0usize..2 {
+ for x in 0usize..2 {
+ let i = x + y * 2;
+ let urb: &[i32; 16] = resdata[16 * 16 + i * 16..][..16].try_into().unwrap();
+
+ let y0 = 1 + y * 4;
+ let x0 = 1 + x * 4;
+ add_residue(&mut uws, urb, y0, x0, stride);
+
+ let vrb: &[i32; 16] = resdata[20 * 16 + i * 16..][..16].try_into().unwrap();
+
+ add_residue(&mut vws, vrb, y0, x0, stride);
+ }
+ }
+
+ for y in 0usize..ylength {
+ for x in 0usize..xlength {
+ self.frame.ubuf[(mby * 8 + y) * w + mbx * 8 + x] = uws[(1 + y) * stride + 1 + x];
+ self.frame.vbuf[(mby * 8 + y) * w + mbx * 8 + x] = vws[(1 + y) * stride + 1 + x];
+ }
+ }
+ }
+
+ fn read_coefficients(
+ &mut self,
+ block: &mut [i32],
+ p: usize,
+ plane: usize,
+ complexity: usize,
+ dcq: i16,
+ acq: i16,
+ ) -> bool {
+ let first = if plane == 0 { 1usize } else { 0usize };
+ let probs = &self.token_probs[plane];
+ let tree = &DCT_TOKEN_TREE;
+
+ let mut complexity = complexity;
+ let mut has_coefficients = false;
+ let mut skip = false;
+
+ for i in first..16usize {
+ let table = &probs[COEFF_BANDS[i] as usize][complexity];
+
+ let token = if !skip {
+ self.partitions[p].read_with_tree(tree, table, 0)
+ } else {
+ self.partitions[p].read_with_tree(tree, table, 2)
+ };
+
+ let mut abs_value = i32::from(match token {
+ DCT_EOB => break,
+
+ DCT_0 => {
+ skip = true;
+ has_coefficients = true;
+ complexity = 0;
+ continue;
+ }
+
+ literal @ DCT_1..=DCT_4 => i16::from(literal),
+
+ category @ DCT_CAT1..=DCT_CAT6 => {
+ let t = PROB_DCT_CAT[(category - DCT_CAT1) as usize];
+
+ let mut extra = 0i16;
+ let mut j = 0;
+
+ while t[j] > 0 {
+ extra = extra + extra + self.partitions[p].read_bool(t[j]) as i16;
+ j += 1;
+ }
+
+ i16::from(DCT_CAT_BASE[(category - DCT_CAT1) as usize]) + extra
+ }
+
+ c => panic!("unknown token: {}", c),
+ });
+
+ skip = false;
+
+ complexity = if abs_value == 0 {
+ 0
+ } else if abs_value == 1 {
+ 1
+ } else {
+ 2
+ };
+
+ if self.partitions[p].read_bool(128) {
+ abs_value = -abs_value;
+ }
+
+ block[ZIGZAG[i] as usize] =
+ abs_value * i32::from(if ZIGZAG[i] > 0 { acq } else { dcq });
+
+ has_coefficients = true;
+ }
+
+ has_coefficients
+ }
+
+ fn read_residual_data(&mut self, mb: &MacroBlock, mbx: usize, p: usize) -> [i32; 384] {
+ let sindex = mb.segmentid as usize;
+ let mut blocks = [0i32; 384];
+ let mut plane = if mb.luma_mode == LumaMode::B { 3 } else { 1 };
+
+ if plane == 1 {
+ let complexity = self.top[mbx].complexity[0] + self.left.complexity[0];
+ let mut block = [0i32; 16];
+ let dcq = self.segment[sindex].y2dc;
+ let acq = self.segment[sindex].y2ac;
+ let n = self.read_coefficients(&mut block, p, plane, complexity as usize, dcq, acq);
+
+ self.left.complexity[0] = if n { 1 } else { 0 };
+ self.top[mbx].complexity[0] = if n { 1 } else { 0 };
+
+ transform::iwht4x4(&mut block);
+
+ for k in 0usize..16 {
+ blocks[16 * k] = block[k];
+ }
+
+ plane = 0;
+ }
+
+ for y in 0usize..4 {
+ let mut left = self.left.complexity[y + 1];
+ for x in 0usize..4 {
+ let i = x + y * 4;
+ let block = &mut blocks[i * 16..i * 16 + 16];
+
+ let complexity = self.top[mbx].complexity[x + 1] + left;
+ let dcq = self.segment[sindex].ydc;
+ let acq = self.segment[sindex].yac;
+
+ let n = self.read_coefficients(block, p, plane, complexity as usize, dcq, acq);
+
+ if block[0] != 0 || n {
+ transform::idct4x4(block);
+ }
+
+ left = if n { 1 } else { 0 };
+ self.top[mbx].complexity[x + 1] = if n { 1 } else { 0 };
+ }
+
+ self.left.complexity[y + 1] = left;
+ }
+
+ plane = 2;
+
+ for &j in &[5usize, 7usize] {
+ for y in 0usize..2 {
+ let mut left = self.left.complexity[y + j];
+
+ for x in 0usize..2 {
+ let i = x + y * 2 + if j == 5 { 16 } else { 20 };
+ let block = &mut blocks[i * 16..i * 16 + 16];
+
+ let complexity = self.top[mbx].complexity[x + j] + left;
+ let dcq = self.segment[sindex].uvdc;
+ let acq = self.segment[sindex].uvac;
+
+ let n = self.read_coefficients(block, p, plane, complexity as usize, dcq, acq);
+ if block[0] != 0 || n {
+ transform::idct4x4(block);
+ }
+
+ left = if n { 1 } else { 0 };
+ self.top[mbx].complexity[x + j] = if n { 1 } else { 0 };
+ }
+
+ self.left.complexity[y + j] = left;
+ }
+ }
+
+ blocks
+ }
+
+ /// Does loop filtering on the macroblock
+ fn loop_filter(&mut self, mbx: usize, mby: usize, mb: &MacroBlock) {
+ let luma_w = self.frame.width as usize;
+ let luma_h = self.frame.height as usize;
+ let chroma_w = self.frame.chroma_width() as usize;
+ let chroma_h = self.frame.chroma_height() as usize;
+
+ let (filter_level, interior_limit, hev_threshold) = self.calculate_filter_parameters(mb);
+
+ if filter_level > 0 {
+ let mbedge_limit = (filter_level + 2) * 2 + interior_limit;
+ let sub_bedge_limit = (filter_level * 2) + interior_limit;
+
+ let luma_ylength = cmp::min(luma_h - 16 * mby, 16);
+ let luma_xlength = cmp::min(luma_w - 16 * mbx, 16);
+
+ let chroma_ylength = cmp::min(chroma_h - 8 * mby, 8);
+ let chroma_xlength = cmp::min(chroma_w - 8 * mbx, 8);
+
+ //filter across left of macroblock
+ if mbx > 0 {
+ //simple loop filtering
+ if self.frame.filter_type {
+ if luma_xlength >= 2 {
+ for y in 0usize..luma_ylength {
+ let y0 = mby * 16 + y;
+ let x0 = mbx * 16;
+
+ loop_filter::simple_segment(
+ mbedge_limit,
+ &mut self.frame.ybuf[..],
+ y0 * luma_w + x0,
+ 1,
+ );
+ }
+ }
+ } else {
+ if luma_xlength >= 4 {
+ for y in 0usize..luma_ylength {
+ let y0 = mby * 16 + y;
+ let x0 = mbx * 16;
+
+ loop_filter::macroblock_filter(
+ hev_threshold,
+ interior_limit,
+ mbedge_limit,
+ &mut self.frame.ybuf[..],
+ y0 * luma_w + x0,
+ 1,
+ );
+ }
+ }
+
+ if chroma_xlength >= 4 {
+ for y in 0usize..chroma_ylength {
+ let y0 = mby * 8 + y;
+ let x0 = mbx * 8;
+
+ loop_filter::macroblock_filter(
+ hev_threshold,
+ interior_limit,
+ mbedge_limit,
+ &mut self.frame.ubuf[..],
+ y0 * chroma_w + x0,
+ 1,
+ );
+ loop_filter::macroblock_filter(
+ hev_threshold,
+ interior_limit,
+ mbedge_limit,
+ &mut self.frame.vbuf[..],
+ y0 * chroma_w + x0,
+ 1,
+ );
+ }
+ }
+ }
+ }
+
+ //filter across vertical subblocks in macroblock
+ if mb.luma_mode == LumaMode::B || !mb.coeffs_skipped {
+ if self.frame.filter_type {
+ for x in (4usize..luma_xlength - 1).step_by(4) {
+ for y in 0..luma_ylength {
+ let y0 = mby * 16 + y;
+ let x0 = mbx * 16 + x;
+
+ loop_filter::simple_segment(
+ sub_bedge_limit,
+ &mut self.frame.ybuf[..],
+ y0 * luma_w + x0,
+ 1,
+ );
+ }
+ }
+ } else {
+ if luma_xlength > 3 {
+ for x in (4usize..luma_xlength - 3).step_by(4) {
+ for y in 0..luma_ylength {
+ let y0 = mby * 16 + y;
+ let x0 = mbx * 16 + x;
+
+ loop_filter::subblock_filter(
+ hev_threshold,
+ interior_limit,
+ sub_bedge_limit,
+ &mut self.frame.ybuf[..],
+ y0 * luma_w + x0,
+ 1,
+ );
+ }
+ }
+ }
+
+ if chroma_xlength == 8 {
+ for y in 0usize..chroma_ylength {
+ let y0 = mby * 8 + y;
+ let x0 = mbx * 8 + 4;
+
+ loop_filter::subblock_filter(
+ hev_threshold,
+ interior_limit,
+ sub_bedge_limit,
+ &mut self.frame.ubuf[..],
+ y0 * chroma_w + x0,
+ 1,
+ );
+
+ loop_filter::subblock_filter(
+ hev_threshold,
+ interior_limit,
+ sub_bedge_limit,
+ &mut self.frame.vbuf[..],
+ y0 * chroma_w + x0,
+ 1,
+ );
+ }
+ }
+ }
+ }
+
+ //filter across top of macroblock
+ if mby > 0 {
+ if self.frame.filter_type {
+ if luma_ylength >= 2 {
+ for x in 0usize..luma_xlength {
+ let y0 = mby * 16;
+ let x0 = mbx * 16 + x;
+
+ loop_filter::simple_segment(
+ mbedge_limit,
+ &mut self.frame.ybuf[..],
+ y0 * luma_w + x0,
+ luma_w,
+ );
+ }
+ }
+ } else {
+ //if bottom macroblock, can only filter if there is 3 pixels below
+ if luma_ylength >= 4 {
+ for x in 0usize..luma_xlength {
+ let y0 = mby * 16;
+ let x0 = mbx * 16 + x;
+
+ loop_filter::macroblock_filter(
+ hev_threshold,
+ interior_limit,
+ mbedge_limit,
+ &mut self.frame.ybuf[..],
+ y0 * luma_w + x0,
+ luma_w,
+ );
+ }
+ }
+
+ if chroma_ylength >= 4 {
+ for x in 0usize..chroma_xlength {
+ let y0 = mby * 8;
+ let x0 = mbx * 8 + x;
+
+ loop_filter::macroblock_filter(
+ hev_threshold,
+ interior_limit,
+ mbedge_limit,
+ &mut self.frame.ubuf[..],
+ y0 * chroma_w + x0,
+ chroma_w,
+ );
+ loop_filter::macroblock_filter(
+ hev_threshold,
+ interior_limit,
+ mbedge_limit,
+ &mut self.frame.vbuf[..],
+ y0 * chroma_w + x0,
+ chroma_w,
+ );
+ }
+ }
+ }
+ }
+
+ //filter across horizontal subblock edges within the macroblock
+ if mb.luma_mode == LumaMode::B || !mb.coeffs_skipped {
+ if self.frame.filter_type {
+ for y in (4usize..luma_ylength - 1).step_by(4) {
+ for x in 0..luma_xlength {
+ let y0 = mby * 16 + y;
+ let x0 = mbx * 16 + x;
+
+ loop_filter::simple_segment(
+ sub_bedge_limit,
+ &mut self.frame.ybuf[..],
+ y0 * luma_w + x0,
+ luma_w,
+ );
+ }
+ }
+ } else {
+ if luma_ylength > 3 {
+ for y in (4usize..luma_ylength - 3).step_by(4) {
+ for x in 0..luma_xlength {
+ let y0 = mby * 16 + y;
+ let x0 = mbx * 16 + x;
+
+ loop_filter::subblock_filter(
+ hev_threshold,
+ interior_limit,
+ sub_bedge_limit,
+ &mut self.frame.ybuf[..],
+ y0 * luma_w + x0,
+ luma_w,
+ );
+ }
+ }
+ }
+
+ if chroma_ylength == 8 {
+ for x in 0..chroma_xlength {
+ let y0 = mby * 8 + 4;
+ let x0 = mbx * 8 + x;
+
+ loop_filter::subblock_filter(
+ hev_threshold,
+ interior_limit,
+ sub_bedge_limit,
+ &mut self.frame.ubuf[..],
+ y0 * chroma_w + x0,
+ chroma_w,
+ );
+
+ loop_filter::subblock_filter(
+ hev_threshold,
+ interior_limit,
+ sub_bedge_limit,
+ &mut self.frame.vbuf[..],
+ y0 * chroma_w + x0,
+ chroma_w,
+ );
+ }
+ }
+ }
+ }
+ }
+ }
+
+ //return values are the filter level, interior limit and hev threshold
+ fn calculate_filter_parameters(&self, macroblock: &MacroBlock) -> (u8, u8, u8) {
+ let segment = self.segment[macroblock.segmentid as usize];
+ let mut filter_level = self.frame.filter_level as i32;
+
+ if self.segments_enabled {
+ if segment.delta_values {
+ filter_level += i32::from(segment.loopfilter_level);
+ } else {
+ filter_level = i32::from(segment.loopfilter_level);
+ }
+ }
+
+ filter_level = clamp(filter_level, 0, 63);
+
+ if macroblock.luma_mode == LumaMode::B {
+ filter_level += self.mode_delta[0];
+ }
+
+ let filter_level = clamp(filter_level, 0, 63) as u8;
+
+ //interior limit
+ let mut interior_limit = filter_level;
+
+ if self.frame.sharpness_level > 0 {
+ interior_limit >>= if self.frame.sharpness_level > 4 { 2 } else { 1 };
+
+ if interior_limit > 9 - self.frame.sharpness_level {
+ interior_limit = 9 - self.frame.sharpness_level;
+ }
+ }
+
+ if interior_limit == 0 {
+ interior_limit = 1;
+ }
+
+ //high edge variance threshold
+ let mut hev_threshold = 0;
+
+ #[allow(clippy::collapsible_else_if)]
+ if self.frame.keyframe {
+ if filter_level >= 40 {
+ hev_threshold = 2;
+ } else {
+ hev_threshold = 1;
+ }
+ } else {
+ if filter_level >= 40 {
+ hev_threshold = 3;
+ } else if filter_level >= 20 {
+ hev_threshold = 2;
+ } else if filter_level >= 15 {
+ hev_threshold = 1;
+ }
+ }
+
+ (filter_level, interior_limit, hev_threshold)
+ }
+
+ /// Decodes the current frame
+ pub fn decode_frame(&mut self) -> ImageResult<&Frame> {
+ self.read_frame_header()?;
+
+ for mby in 0..self.mbheight as usize {
+ let p = mby % self.num_partitions as usize;
+ self.left = MacroBlock::default();
+
+ for mbx in 0..self.mbwidth as usize {
+ let mb = self.read_macroblock_header(mbx)?;
+ let blocks = if !mb.coeffs_skipped {
+ self.read_residual_data(&mb, mbx, p)
+ } else {
+ if mb.luma_mode != LumaMode::B {
+ self.left.complexity[0] = 0;
+ self.top[mbx].complexity[0] = 0;
+ }
+
+ for i in 1usize..9 {
+ self.left.complexity[i] = 0;
+ self.top[mbx].complexity[i] = 0;
+ }
+
+ [0i32; 384]
+ };
+
+ self.intra_predict_luma(mbx, mby, &mb, &blocks);
+ self.intra_predict_chroma(mbx, mby, &mb, &blocks);
+
+ self.macroblocks.push(mb);
+ }
+
+ self.left_border = vec![129u8; 1 + 16];
+ }
+
+ //do loop filtering
+ for mby in 0..self.mbheight as usize {
+ for mbx in 0..self.mbwidth as usize {
+ let mb = self.macroblocks[mby * self.mbwidth as usize + mbx];
+ self.loop_filter(mbx, mby, &mb);
+ }
+ }
+
+ Ok(&self.frame)
+ }
+}
+
+impl LumaMode {
+ fn from_i8(val: i8) -> Option<Self> {
+ Some(match val {
+ DC_PRED => LumaMode::DC,
+ V_PRED => LumaMode::V,
+ H_PRED => LumaMode::H,
+ TM_PRED => LumaMode::TM,
+ B_PRED => LumaMode::B,
+ _ => return None,
+ })
+ }
+
+ fn into_intra(self) -> Option<IntraMode> {
+ Some(match self {
+ LumaMode::DC => IntraMode::DC,
+ LumaMode::V => IntraMode::VE,
+ LumaMode::H => IntraMode::HE,
+ LumaMode::TM => IntraMode::TM,
+ LumaMode::B => return None,
+ })
+ }
+}
+
+impl Default for LumaMode {
+ fn default() -> Self {
+ LumaMode::DC
+ }
+}
+
+impl ChromaMode {
+ fn from_i8(val: i8) -> Option<Self> {
+ Some(match val {
+ DC_PRED => ChromaMode::DC,
+ V_PRED => ChromaMode::V,
+ H_PRED => ChromaMode::H,
+ TM_PRED => ChromaMode::TM,
+ _ => return None,
+ })
+ }
+}
+
+impl Default for ChromaMode {
+ fn default() -> Self {
+ ChromaMode::DC
+ }
+}
+
+impl IntraMode {
+ fn from_i8(val: i8) -> Option<Self> {
+ Some(match val {
+ B_DC_PRED => IntraMode::DC,
+ B_TM_PRED => IntraMode::TM,
+ B_VE_PRED => IntraMode::VE,
+ B_HE_PRED => IntraMode::HE,
+ B_LD_PRED => IntraMode::LD,
+ B_RD_PRED => IntraMode::RD,
+ B_VR_PRED => IntraMode::VR,
+ B_VL_PRED => IntraMode::VL,
+ B_HD_PRED => IntraMode::HD,
+ B_HU_PRED => IntraMode::HU,
+ _ => return None,
+ })
+ }
+}
+
+impl Default for IntraMode {
+ fn default() -> Self {
+ IntraMode::DC
+ }
+}
+
+fn init_top_macroblocks(width: usize) -> Vec<MacroBlock> {
+ let mb_width = (width + 15) / 16;
+
+ let mb = MacroBlock {
+ // Section 11.3 #3
+ bpred: [IntraMode::DC; 16],
+ luma_mode: LumaMode::DC,
+ ..MacroBlock::default()
+ };
+
+ vec![mb; mb_width]
+}
+
+fn create_border_luma(mbx: usize, mby: usize, mbw: usize, top: &[u8], left: &[u8]) -> [u8; 357] {
+ let stride = 1usize + 16 + 4;
+ let mut ws = [0u8; (1 + 16) * (1 + 16 + 4)];
+
+ // A
+ {
+ let above = &mut ws[1..stride];
+ if mby == 0 {
+ for above in above.iter_mut() {
+ *above = 127;
+ }
+ } else {
+ for i in 0usize..16 {
+ above[i] = top[mbx * 16 + i];
+ }
+
+ if mbx == mbw - 1 {
+ for above in above.iter_mut().skip(16) {
+ *above = top[mbx * 16 + 15];
+ }
+ } else {
+ for i in 16usize..above.len() {
+ above[i] = top[mbx * 16 + i];
+ }
+ }
+ }
+ }
+
+ for i in 17usize..stride {
+ ws[4 * stride + i] = ws[i];
+ ws[8 * stride + i] = ws[i];
+ ws[12 * stride + i] = ws[i];
+ }
+
+ // L
+ if mbx == 0 {
+ for i in 0usize..16 {
+ ws[(i + 1) * stride] = 129;
+ }
+ } else {
+ for i in 0usize..16 {
+ ws[(i + 1) * stride] = left[i + 1];
+ }
+ }
+
+ // P
+ ws[0] = if mby == 0 {
+ 127
+ } else if mbx == 0 {
+ 129
+ } else {
+ left[0]
+ };
+
+ ws
+}
+
+fn avg3(left: u8, this: u8, right: u8) -> u8 {
+ let avg = (u16::from(left) + 2 * u16::from(this) + u16::from(right) + 2) >> 2;
+ avg as u8
+}
+
+fn avg2(this: u8, right: u8) -> u8 {
+ let avg = (u16::from(this) + u16::from(right) + 1) >> 1;
+ avg as u8
+}
+
+// Only 16 elements from rblock are used to add residue, so it is restricted to 16 elements
+// to enable SIMD and other optimizations.
+fn add_residue(pblock: &mut [u8], rblock: &[i32; 16], y0: usize, x0: usize, stride: usize) {
+ let mut pos = y0 * stride + x0;
+ for row in rblock.chunks(4) {
+ for (p, &a) in pblock[pos..pos + 4].iter_mut().zip(row.iter()) {
+ *p = clamp(a + i32::from(*p), 0, 255) as u8;
+ }
+ pos += stride;
+ }
+}
+
+fn predict_4x4(ws: &mut [u8], stride: usize, modes: &[IntraMode], resdata: &[i32]) {
+ for sby in 0usize..4 {
+ for sbx in 0usize..4 {
+ let i = sbx + sby * 4;
+ let y0 = sby * 4 + 1;
+ let x0 = sbx * 4 + 1;
+
+ match modes[i] {
+ IntraMode::TM => predict_tmpred(ws, 4, x0, y0, stride),
+ IntraMode::VE => predict_bvepred(ws, x0, y0, stride),
+ IntraMode::HE => predict_bhepred(ws, x0, y0, stride),
+ IntraMode::DC => predict_bdcpred(ws, x0, y0, stride),
+ IntraMode::LD => predict_bldpred(ws, x0, y0, stride),
+ IntraMode::RD => predict_brdpred(ws, x0, y0, stride),
+ IntraMode::VR => predict_bvrpred(ws, x0, y0, stride),
+ IntraMode::VL => predict_bvlpred(ws, x0, y0, stride),
+ IntraMode::HD => predict_bhdpred(ws, x0, y0, stride),
+ IntraMode::HU => predict_bhupred(ws, x0, y0, stride),
+ }
+
+ let rb: &[i32; 16] = resdata[i * 16..][..16].try_into().unwrap();
+ add_residue(ws, rb, y0, x0, stride);
+ }
+ }
+}
+
+fn predict_vpred(a: &mut [u8], size: usize, x0: usize, y0: usize, stride: usize) {
+ for y in 0usize..size {
+ for x in 0usize..size {
+ a[(x + x0) + stride * (y + y0)] = a[(x + x0) + stride * (y0 + y - 1)];
+ }
+ }
+}
+
+fn predict_hpred(a: &mut [u8], size: usize, x0: usize, y0: usize, stride: usize) {
+ for y in 0usize..size {
+ for x in 0usize..size {
+ a[(x + x0) + stride * (y + y0)] = a[(x + x0 - 1) + stride * (y0 + y)];
+ }
+ }
+}
+
+fn predict_dcpred(a: &mut [u8], size: usize, stride: usize, above: bool, left: bool) {
+ let mut sum = 0;
+ let mut shf = if size == 8 { 2 } else { 3 };
+
+ if left {
+ for y in 0usize..size {
+ sum += u32::from(a[(y + 1) * stride]);
+ }
+
+ shf += 1;
+ }
+
+ if above {
+ for x in 0usize..size {
+ sum += u32::from(a[x + 1]);
+ }
+
+ shf += 1;
+ }
+
+ let dcval = if !left && !above {
+ 128
+ } else {
+ (sum + (1 << (shf - 1))) >> shf
+ };
+
+ for y in 0usize..size {
+ for x in 0usize..size {
+ a[(x + 1) + stride * (y + 1)] = dcval as u8;
+ }
+ }
+}
+
+fn predict_tmpred(a: &mut [u8], size: usize, x0: usize, y0: usize, stride: usize) {
+ for y in 0usize..size {
+ for x in 0usize..size {
+ let pred = i32::from(a[(y0 + y) * stride + x0 - 1])
+ + i32::from(a[(y0 - 1) * stride + x0 + x])
+ - i32::from(a[(y0 - 1) * stride + x0 - 1]);
+
+ a[(x + x0) + stride * (y + y0)] = clamp(pred, 0, 255) as u8;
+ }
+ }
+}
+
+fn predict_bdcpred(a: &mut [u8], x0: usize, y0: usize, stride: usize) {
+ let mut v = 4;
+ for i in 0usize..4 {
+ v += u32::from(a[(y0 + i) * stride + x0 - 1]) + u32::from(a[(y0 - 1) * stride + x0 + i]);
+ }
+
+ v >>= 3;
+ for y in 0usize..4 {
+ for x in 0usize..4 {
+ a[x + x0 + stride * (y + y0)] = v as u8;
+ }
+ }
+}
+
+fn topleft_pixel(a: &[u8], x0: usize, y0: usize, stride: usize) -> u8 {
+ a[(y0 - 1) * stride + x0 - 1]
+}
+
+fn top_pixels(a: &[u8], x0: usize, y0: usize, stride: usize) -> (u8, u8, u8, u8, u8, u8, u8, u8) {
+ let pos = (y0 - 1) * stride + x0;
+ let a_slice = &a[pos..pos + 8];
+ let a0 = a_slice[0];
+ let a1 = a_slice[1];
+ let a2 = a_slice[2];
+ let a3 = a_slice[3];
+ let a4 = a_slice[4];
+ let a5 = a_slice[5];
+ let a6 = a_slice[6];
+ let a7 = a_slice[7];
+
+ (a0, a1, a2, a3, a4, a5, a6, a7)
+}
+
+fn left_pixels(a: &[u8], x0: usize, y0: usize, stride: usize) -> (u8, u8, u8, u8) {
+ let l0 = a[y0 * stride + x0 - 1];
+ let l1 = a[(y0 + 1) * stride + x0 - 1];
+ let l2 = a[(y0 + 2) * stride + x0 - 1];
+ let l3 = a[(y0 + 3) * stride + x0 - 1];
+
+ (l0, l1, l2, l3)
+}
+
+fn edge_pixels(
+ a: &[u8],
+ x0: usize,
+ y0: usize,
+ stride: usize,
+) -> (u8, u8, u8, u8, u8, u8, u8, u8, u8) {
+ let pos = (y0 - 1) * stride + x0 - 1;
+ let a_slice = &a[pos..=pos + 4];
+ let e0 = a[pos + 4 * stride];
+ let e1 = a[pos + 3 * stride];
+ let e2 = a[pos + 2 * stride];
+ let e3 = a[pos + stride];
+ let e4 = a_slice[0];
+ let e5 = a_slice[1];
+ let e6 = a_slice[2];
+ let e7 = a_slice[3];
+ let e8 = a_slice[4];
+
+ (e0, e1, e2, e3, e4, e5, e6, e7, e8)
+}
+
+fn predict_bvepred(a: &mut [u8], x0: usize, y0: usize, stride: usize) {
+ let p = topleft_pixel(a, x0, y0, stride);
+ let (a0, a1, a2, a3, a4, _, _, _) = top_pixels(a, x0, y0, stride);
+ let avg_1 = avg3(p, a0, a1);
+ let avg_2 = avg3(a0, a1, a2);
+ let avg_3 = avg3(a1, a2, a3);
+ let avg_4 = avg3(a2, a3, a4);
+
+ let avg = [avg_1, avg_2, avg_3, avg_4];
+
+ let mut pos = y0 * stride + x0;
+ for _ in 0..4 {
+ a[pos..=pos + 3].copy_from_slice(&avg);
+ pos += stride;
+ }
+}
+
+fn predict_bhepred(a: &mut [u8], x0: usize, y0: usize, stride: usize) {
+ let p = topleft_pixel(a, x0, y0, stride);
+ let (l0, l1, l2, l3) = left_pixels(a, x0, y0, stride);
+
+ let avgs = [
+ avg3(p, l0, l1),
+ avg3(l0, l1, l2),
+ avg3(l1, l2, l3),
+ avg3(l2, l3, l3),
+ ];
+
+ let mut pos = y0 * stride + x0;
+ for &avg in avgs.iter() {
+ for a_p in a[pos..=pos + 3].iter_mut() {
+ *a_p = avg;
+ }
+ pos += stride;
+ }
+}
+
+fn predict_bldpred(a: &mut [u8], x0: usize, y0: usize, stride: usize) {
+ let (a0, a1, a2, a3, a4, a5, a6, a7) = top_pixels(a, x0, y0, stride);
+
+ let avgs = [
+ avg3(a0, a1, a2),
+ avg3(a1, a2, a3),
+ avg3(a2, a3, a4),
+ avg3(a3, a4, a5),
+ avg3(a4, a5, a6),
+ avg3(a5, a6, a7),
+ avg3(a6, a7, a7),
+ ];
+
+ let mut pos = y0 * stride + x0;
+
+ for i in 0..4 {
+ a[pos..=pos + 3].copy_from_slice(&avgs[i..=i + 3]);
+ pos += stride;
+ }
+}
+
+fn predict_brdpred(a: &mut [u8], x0: usize, y0: usize, stride: usize) {
+ let (e0, e1, e2, e3, e4, e5, e6, e7, e8) = edge_pixels(a, x0, y0, stride);
+
+ let avgs = [
+ avg3(e0, e1, e2),
+ avg3(e1, e2, e3),
+ avg3(e2, e3, e4),
+ avg3(e3, e4, e5),
+ avg3(e4, e5, e6),
+ avg3(e5, e6, e7),
+ avg3(e6, e7, e8),
+ ];
+ let mut pos = y0 * stride + x0;
+
+ for i in 0..4 {
+ a[pos..=pos + 3].copy_from_slice(&avgs[3 - i..7 - i]);
+ pos += stride;
+ }
+}
+
+fn predict_bvrpred(a: &mut [u8], x0: usize, y0: usize, stride: usize) {
+ let (_, e1, e2, e3, e4, e5, e6, e7, e8) = edge_pixels(a, x0, y0, stride);
+
+ a[(y0 + 3) * stride + x0] = avg3(e1, e2, e3);
+ a[(y0 + 2) * stride + x0] = avg3(e2, e3, e4);
+ a[(y0 + 3) * stride + x0 + 1] = avg3(e3, e4, e5);
+ a[(y0 + 1) * stride + x0] = avg3(e3, e4, e5);
+ a[(y0 + 2) * stride + x0 + 1] = avg2(e4, e5);
+ a[y0 * stride + x0] = avg2(e4, e5);
+ a[(y0 + 3) * stride + x0 + 2] = avg3(e4, e5, e6);
+ a[(y0 + 1) * stride + x0 + 1] = avg3(e4, e5, e6);
+ a[(y0 + 2) * stride + x0 + 2] = avg2(e5, e6);
+ a[y0 * stride + x0 + 1] = avg2(e5, e6);
+ a[(y0 + 3) * stride + x0 + 3] = avg3(e5, e6, e7);
+ a[(y0 + 1) * stride + x0 + 2] = avg3(e5, e6, e7);
+ a[(y0 + 2) * stride + x0 + 3] = avg2(e6, e7);
+ a[y0 * stride + x0 + 2] = avg2(e6, e7);
+ a[(y0 + 1) * stride + x0 + 3] = avg3(e6, e7, e8);
+ a[y0 * stride + x0 + 3] = avg2(e7, e8);
+}
+
+fn predict_bvlpred(a: &mut [u8], x0: usize, y0: usize, stride: usize) {
+ let (a0, a1, a2, a3, a4, a5, a6, a7) = top_pixels(a, x0, y0, stride);
+
+ a[y0 * stride + x0] = avg2(a0, a1);
+ a[(y0 + 1) * stride + x0] = avg3(a0, a1, a2);
+ a[(y0 + 2) * stride + x0] = avg2(a1, a2);
+ a[y0 * stride + x0 + 1] = avg2(a1, a2);
+ a[(y0 + 1) * stride + x0 + 1] = avg3(a1, a2, a3);
+ a[(y0 + 3) * stride + x0] = avg3(a1, a2, a3);
+ a[(y0 + 2) * stride + x0 + 1] = avg2(a2, a3);
+ a[y0 * stride + x0 + 2] = avg2(a2, a3);
+ a[(y0 + 3) * stride + x0 + 1] = avg3(a2, a3, a4);
+ a[(y0 + 1) * stride + x0 + 2] = avg3(a2, a3, a4);
+ a[(y0 + 2) * stride + x0 + 2] = avg2(a3, a4);
+ a[y0 * stride + x0 + 3] = avg2(a3, a4);
+ a[(y0 + 3) * stride + x0 + 2] = avg3(a3, a4, a5);
+ a[(y0 + 1) * stride + x0 + 3] = avg3(a3, a4, a5);
+ a[(y0 + 2) * stride + x0 + 3] = avg3(a4, a5, a6);
+ a[(y0 + 3) * stride + x0 + 3] = avg3(a5, a6, a7);
+}
+
+fn predict_bhdpred(a: &mut [u8], x0: usize, y0: usize, stride: usize) {
+ let (e0, e1, e2, e3, e4, e5, e6, e7, _) = edge_pixels(a, x0, y0, stride);
+
+ a[(y0 + 3) * stride + x0] = avg2(e0, e1);
+ a[(y0 + 3) * stride + x0 + 1] = avg3(e0, e1, e2);
+ a[(y0 + 2) * stride + x0] = avg2(e1, e2);
+ a[(y0 + 3) * stride + x0 + 2] = avg2(e1, e2);
+ a[(y0 + 2) * stride + x0 + 1] = avg3(e1, e2, e3);
+ a[(y0 + 3) * stride + x0 + 3] = avg3(e1, e2, e3);
+ a[(y0 + 2) * stride + x0 + 2] = avg2(e2, e3);
+ a[(y0 + 1) * stride + x0] = avg2(e2, e3);
+ a[(y0 + 2) * stride + x0 + 3] = avg3(e2, e3, e4);
+ a[(y0 + 1) * stride + x0 + 1] = avg3(e2, e3, e4);
+ a[(y0 + 1) * stride + x0 + 2] = avg2(e3, e4);
+ a[y0 * stride + x0] = avg2(e3, e4);
+ a[(y0 + 1) * stride + x0 + 3] = avg3(e3, e4, e5);
+ a[y0 * stride + x0 + 1] = avg3(e3, e4, e5);
+ a[y0 * stride + x0 + 2] = avg3(e4, e5, e6);
+ a[y0 * stride + x0 + 3] = avg3(e5, e6, e7);
+}
+
+fn predict_bhupred(a: &mut [u8], x0: usize, y0: usize, stride: usize) {
+ let (l0, l1, l2, l3) = left_pixels(a, x0, y0, stride);
+
+ a[y0 * stride + x0] = avg2(l0, l1);
+ a[y0 * stride + x0 + 1] = avg3(l0, l1, l2);
+ a[y0 * stride + x0 + 2] = avg2(l1, l2);
+ a[(y0 + 1) * stride + x0] = avg2(l1, l2);
+ a[y0 * stride + x0 + 3] = avg3(l1, l2, l3);
+ a[(y0 + 1) * stride + x0 + 1] = avg3(l1, l2, l3);
+ a[(y0 + 1) * stride + x0 + 2] = avg2(l2, l3);
+ a[(y0 + 2) * stride + x0] = avg2(l2, l3);
+ a[(y0 + 1) * stride + x0 + 3] = avg3(l2, l3, l3);
+ a[(y0 + 2) * stride + x0 + 1] = avg3(l2, l3, l3);
+ a[(y0 + 2) * stride + x0 + 2] = l3;
+ a[(y0 + 2) * stride + x0 + 3] = l3;
+ a[(y0 + 3) * stride + x0] = l3;
+ a[(y0 + 3) * stride + x0 + 1] = l3;
+ a[(y0 + 3) * stride + x0 + 2] = l3;
+ a[(y0 + 3) * stride + x0 + 3] = l3;
+}
+
+#[cfg(test)]
+mod test {
+
+ #[cfg(feature = "benchmarks")]
+ extern crate test;
+ use super::{
+ add_residue, avg2, avg3, edge_pixels, predict_bhepred, predict_bldpred, predict_brdpred,
+ predict_bvepred, top_pixels,
+ };
+ #[cfg(feature = "benchmarks")]
+ use super::{predict_4x4, IntraMode};
+ #[cfg(feature = "benchmarks")]
+ use test::{black_box, Bencher};
+
+ #[cfg(feature = "benchmarks")]
+ const W: usize = 256;
+ #[cfg(feature = "benchmarks")]
+ const H: usize = 256;
+
+ #[cfg(feature = "benchmarks")]
+ fn make_sample_image() -> Vec<u8> {
+ let mut v = Vec::with_capacity((W * H * 4) as usize);
+ for c in 0u8..=255 {
+ for k in 0u8..=255 {
+ v.push(c);
+ v.push(0);
+ v.push(0);
+ v.push(k);
+ }
+ }
+ v
+ }
+
+ #[cfg(feature = "benchmarks")]
+ #[bench]
+ fn bench_predict_4x4(b: &mut Bencher) {
+ let mut v = black_box(make_sample_image());
+
+ let res_data = vec![1i32; W * H * 4];
+ let modes = [
+ IntraMode::TM,
+ IntraMode::VE,
+ IntraMode::HE,
+ IntraMode::DC,
+ IntraMode::LD,
+ IntraMode::RD,
+ IntraMode::VR,
+ IntraMode::VL,
+ IntraMode::HD,
+ IntraMode::HU,
+ IntraMode::TM,
+ IntraMode::VE,
+ IntraMode::HE,
+ IntraMode::DC,
+ IntraMode::LD,
+ IntraMode::RD,
+ ];
+
+ b.iter(|| {
+ black_box(predict_4x4(&mut v, W * 2, &modes, &res_data));
+ });
+ }
+
+ #[cfg(feature = "benchmarks")]
+ #[bench]
+ fn bench_predict_bvepred(b: &mut Bencher) {
+ let mut v = make_sample_image();
+
+ b.iter(|| {
+ predict_bvepred(black_box(&mut v), 5, 5, W * 2);
+ });
+ }
+
+ #[cfg(feature = "benchmarks")]
+ #[bench]
+ fn bench_predict_bldpred(b: &mut Bencher) {
+ let mut v = black_box(make_sample_image());
+
+ b.iter(|| {
+ black_box(predict_bldpred(black_box(&mut v), 5, 5, W * 2));
+ });
+ }
+
+ #[cfg(feature = "benchmarks")]
+ #[bench]
+ fn bench_predict_brdpred(b: &mut Bencher) {
+ let mut v = black_box(make_sample_image());
+
+ b.iter(|| {
+ black_box(predict_brdpred(black_box(&mut v), 5, 5, W * 2));
+ });
+ }
+
+ #[cfg(feature = "benchmarks")]
+ #[bench]
+ fn bench_predict_bhepred(b: &mut Bencher) {
+ let mut v = black_box(make_sample_image());
+
+ b.iter(|| {
+ black_box(predict_bhepred(black_box(&mut v), 5, 5, W * 2));
+ });
+ }
+
+ #[cfg(feature = "benchmarks")]
+ #[bench]
+ fn bench_top_pixels(b: &mut Bencher) {
+ let v = black_box(make_sample_image());
+
+ b.iter(|| {
+ black_box(top_pixels(black_box(&v), 5, 5, W * 2));
+ });
+ }
+
+ #[cfg(feature = "benchmarks")]
+ #[bench]
+ fn bench_edge_pixels(b: &mut Bencher) {
+ let v = black_box(make_sample_image());
+
+ b.iter(|| {
+ black_box(edge_pixels(black_box(&v), 5, 5, W * 2));
+ });
+ }
+
+ #[test]
+ fn test_avg2() {
+ for i in 0u8..=255 {
+ for j in 0u8..=255 {
+ let ceil_avg = ((i as f32) + (j as f32)) / 2.0;
+ let ceil_avg = ceil_avg.ceil() as u8;
+ assert_eq!(
+ ceil_avg,
+ avg2(i, j),
+ "avg2({}, {}), expected {}, got {}.",
+ i,
+ j,
+ ceil_avg,
+ avg2(i, j)
+ );
+ }
+ }
+ }
+
+ #[test]
+ fn test_avg2_specific() {
+ assert_eq!(
+ 255,
+ avg2(255, 255),
+ "avg2(255, 255), expected 255, got {}.",
+ avg2(255, 255)
+ );
+ assert_eq!(1, avg2(1, 1), "avg2(1, 1), expected 1, got {}.", avg2(1, 1));
+ assert_eq!(2, avg2(2, 1), "avg2(2, 1), expected 2, got {}.", avg2(2, 1));
+ }
+
+ #[test]
+ fn test_avg3() {
+ for i in 0u8..=255 {
+ for j in 0u8..=255 {
+ for k in 0u8..=255 {
+ let floor_avg = ((i as f32) + 2.0 * (j as f32) + { k as f32 } + 2.0) / 4.0;
+ let floor_avg = floor_avg.floor() as u8;
+ assert_eq!(
+ floor_avg,
+ avg3(i, j, k),
+ "avg3({}, {}, {}), expected {}, got {}.",
+ i,
+ j,
+ k,
+ floor_avg,
+ avg3(i, j, k)
+ );
+ }
+ }
+ }
+ }
+
+ #[test]
+ fn test_edge_pixels() {
+ #[rustfmt::skip]
+ let im = vec![5, 6, 7, 8, 9,
+ 4, 0, 0, 0, 0,
+ 3, 0, 0, 0, 0,
+ 2, 0, 0, 0, 0,
+ 1, 0, 0, 0, 0];
+ let (e0, e1, e2, e3, e4, e5, e6, e7, e8) = edge_pixels(&im, 1, 1, 5);
+ assert_eq!(e0, 1);
+ assert_eq!(e1, 2);
+ assert_eq!(e2, 3);
+ assert_eq!(e3, 4);
+ assert_eq!(e4, 5);
+ assert_eq!(e5, 6);
+ assert_eq!(e6, 7);
+ assert_eq!(e7, 8);
+ assert_eq!(e8, 9);
+ }
+
+ #[test]
+ fn test_top_pixels() {
+ #[rustfmt::skip]
+ let im = vec![1, 2, 3, 4, 5, 6, 7, 8,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0];
+ let (e0, e1, e2, e3, e4, e5, e6, e7) = top_pixels(&im, 0, 1, 8);
+ assert_eq!(e0, 1);
+ assert_eq!(e1, 2);
+ assert_eq!(e2, 3);
+ assert_eq!(e3, 4);
+ assert_eq!(e4, 5);
+ assert_eq!(e5, 6);
+ assert_eq!(e6, 7);
+ assert_eq!(e7, 8);
+ }
+
+ #[test]
+ fn test_add_residue() {
+ let mut pblock = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16];
+ let rblock = [
+ -1, -2, -3, -4, 250, 249, 248, 250, -10, -18, -192, -17, -3, 15, 18, 9,
+ ];
+ let expected: [u8; 16] = [0, 0, 0, 0, 255, 255, 255, 255, 0, 0, 0, 0, 10, 29, 33, 25];
+
+ add_residue(&mut pblock, &rblock, 0, 0, 4);
+
+ for (&e, &i) in expected.iter().zip(&pblock) {
+ assert_eq!(e, i);
+ }
+ }
+
+ #[test]
+ fn test_predict_bhepred() {
+ #[rustfmt::skip]
+ let expected: Vec<u8> = vec![5, 0, 0, 0, 0,
+ 4, 4, 4, 4, 4,
+ 3, 3, 3, 3, 3,
+ 2, 2, 2, 2, 2,
+ 1, 1, 1, 1, 1];
+
+ #[rustfmt::skip]
+ let mut im = vec![5, 0, 0, 0, 0,
+ 4, 0, 0, 0, 0,
+ 3, 0, 0, 0, 0,
+ 2, 0, 0, 0, 0,
+ 1, 0, 0, 0, 0];
+ predict_bhepred(&mut im, 1, 1, 5);
+ for (&e, i) in expected.iter().zip(im) {
+ assert_eq!(e, i);
+ }
+ }
+
+ #[test]
+ fn test_predict_brdpred() {
+ #[rustfmt::skip]
+ let expected: Vec<u8> = vec![5, 6, 7, 8, 9,
+ 4, 5, 6, 7, 8,
+ 3, 4, 5, 6, 7,
+ 2, 3, 4, 5, 6,
+ 1, 2, 3, 4, 5];
+
+ #[rustfmt::skip]
+ let mut im = vec![5, 6, 7, 8, 9,
+ 4, 0, 0, 0, 0,
+ 3, 0, 0, 0, 0,
+ 2, 0, 0, 0, 0,
+ 1, 0, 0, 0, 0];
+ predict_brdpred(&mut im, 1, 1, 5);
+ for (&e, i) in expected.iter().zip(im) {
+ assert_eq!(e, i);
+ }
+ }
+
+ #[test]
+ fn test_predict_bldpred() {
+ #[rustfmt::skip]
+ let mut im: Vec<u8> = vec![1, 2, 3, 4, 5, 6, 7, 8,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0];
+ let avg_1 = 2u8;
+ let avg_2 = 3u8;
+ let avg_3 = 4u8;
+ let avg_4 = 5u8;
+ let avg_5 = 6u8;
+ let avg_6 = 7u8;
+ let avg_7 = 8u8;
+
+ predict_bldpred(&mut im, 0, 1, 8);
+
+ assert_eq!(im[8], avg_1);
+ assert_eq!(im[9], avg_2);
+ assert_eq!(im[10], avg_3);
+ assert_eq!(im[11], avg_4);
+ assert_eq!(im[16], avg_2);
+ assert_eq!(im[17], avg_3);
+ assert_eq!(im[18], avg_4);
+ assert_eq!(im[19], avg_5);
+ assert_eq!(im[24], avg_3);
+ assert_eq!(im[25], avg_4);
+ assert_eq!(im[26], avg_5);
+ assert_eq!(im[27], avg_6);
+ assert_eq!(im[32], avg_4);
+ assert_eq!(im[33], avg_5);
+ assert_eq!(im[34], avg_6);
+ assert_eq!(im[35], avg_7);
+ }
+
+ #[test]
+ fn test_predict_bvepred() {
+ #[rustfmt::skip]
+ let mut im: Vec<u8> = vec![1, 2, 3, 4, 5, 6, 7, 8, 9,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0];
+ let avg_1 = 2u8;
+ let avg_2 = 3u8;
+ let avg_3 = 4u8;
+ let avg_4 = 5u8;
+
+ predict_bvepred(&mut im, 1, 1, 9);
+
+ assert_eq!(im[10], avg_1);
+ assert_eq!(im[11], avg_2);
+ assert_eq!(im[12], avg_3);
+ assert_eq!(im[13], avg_4);
+ assert_eq!(im[19], avg_1);
+ assert_eq!(im[20], avg_2);
+ assert_eq!(im[21], avg_3);
+ assert_eq!(im[22], avg_4);
+ assert_eq!(im[28], avg_1);
+ assert_eq!(im[29], avg_2);
+ assert_eq!(im[30], avg_3);
+ assert_eq!(im[31], avg_4);
+ assert_eq!(im[37], avg_1);
+ assert_eq!(im[38], avg_2);
+ assert_eq!(im[39], avg_3);
+ assert_eq!(im[40], avg_4);
+ }
+}
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