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-rw-r--r--vendor/jpeg-decoder/src/decoder/lossless.rs259
1 files changed, 0 insertions, 259 deletions
diff --git a/vendor/jpeg-decoder/src/decoder/lossless.rs b/vendor/jpeg-decoder/src/decoder/lossless.rs
deleted file mode 100644
index 6422220..0000000
--- a/vendor/jpeg-decoder/src/decoder/lossless.rs
+++ /dev/null
@@ -1,259 +0,0 @@
-use std::io::Read;
-use crate::decoder::{Decoder, MAX_COMPONENTS};
-use crate::error::{Error, Result};
-use crate::huffman::HuffmanDecoder;
-use crate::marker::Marker;
-use crate::parser::Predictor;
-use crate::parser::{Component, FrameInfo, ScanInfo};
-
-impl<R: Read> Decoder<R> {
- /// decode_scan_lossless
- pub fn decode_scan_lossless(
- &mut self,
- frame: &FrameInfo,
- scan: &ScanInfo,
- ) -> Result<(Option<Marker>, Vec<Vec<u16>>)> {
- let ncomp = scan.component_indices.len();
- let npixel = frame.image_size.height as usize * frame.image_size.width as usize;
- assert!(ncomp <= MAX_COMPONENTS);
- let mut results = vec![vec![0u16; npixel]; ncomp];
-
- let components: Vec<Component> = scan
- .component_indices
- .iter()
- .map(|&i| frame.components[i].clone())
- .collect();
-
- // Verify that all required huffman tables has been set.
- if scan
- .dc_table_indices
- .iter()
- .any(|&i| self.dc_huffman_tables[i].is_none())
- {
- return Err(Error::Format(
- "scan makes use of unset dc huffman table".to_owned(),
- ));
- }
-
- let mut huffman = HuffmanDecoder::new();
- let reader = &mut self.reader;
- let mut mcus_left_until_restart = self.restart_interval;
- let mut expected_rst_num = 0;
- let mut ra = [0u16; MAX_COMPONENTS];
- let mut rb = [0u16; MAX_COMPONENTS];
- let mut rc = [0u16; MAX_COMPONENTS];
-
- let width = frame.image_size.width as usize;
- let height = frame.image_size.height as usize;
-
- let mut differences = vec![Vec::with_capacity(npixel); ncomp];
- for _mcu_y in 0..height {
- for _mcu_x in 0..width {
- if self.restart_interval > 0 {
- if mcus_left_until_restart == 0 {
- match huffman.take_marker(reader)? {
- Some(Marker::RST(n)) => {
- if n != expected_rst_num {
- return Err(Error::Format(format!(
- "found RST{} where RST{} was expected",
- n, expected_rst_num
- )));
- }
-
- huffman.reset();
-
- expected_rst_num = (expected_rst_num + 1) % 8;
- mcus_left_until_restart = self.restart_interval;
- }
- Some(marker) => {
- return Err(Error::Format(format!(
- "found marker {:?} inside scan where RST{} was expected",
- marker, expected_rst_num
- )))
- }
- None => {
- return Err(Error::Format(format!(
- "no marker found where RST{} was expected",
- expected_rst_num
- )))
- }
- }
- }
-
- mcus_left_until_restart -= 1;
- }
-
- for (i, _component) in components.iter().enumerate() {
- let dc_table = self.dc_huffman_tables[scan.dc_table_indices[i]]
- .as_ref()
- .unwrap();
- let value = huffman.decode(reader, dc_table)?;
- let diff = match value {
- 0 => 0,
- 1..=15 => huffman.receive_extend(reader, value)? as i32,
- 16 => 32768,
- _ => {
- // Section F.1.2.1.1
- // Table F.1
- return Err(Error::Format(
- "invalid DC difference magnitude category".to_owned(),
- ));
- }
- };
- differences[i].push(diff);
- }
- }
- }
-
- if scan.predictor_selection == Predictor::Ra {
- for (i, _component) in components.iter().enumerate() {
- // calculate the top left pixel
- let diff = differences[i][0];
- let prediction = 1 << (frame.precision - scan.point_transform - 1) as i32;
- let result = ((prediction + diff) & 0xFFFF) as u16; // modulo 2^16
- let result = result << scan.point_transform;
- results[i][0] = result;
-
- // calculate leftmost column, using top pixel as predictor
- let mut previous = result;
- for mcu_y in 1..height {
- let diff = differences[i][mcu_y * width];
- let prediction = previous as i32;
- let result = ((prediction + diff) & 0xFFFF) as u16; // modulo 2^16
- let result = result << scan.point_transform;
- results[i][mcu_y * width] = result;
- previous = result;
- }
-
- // calculate rows, using left pixel as predictor
- for mcu_y in 0..height {
- for mcu_x in 1..width {
- let diff = differences[i][mcu_y * width + mcu_x];
- let prediction = results[i][mcu_y * width + mcu_x - 1] as i32;
- let result = ((prediction + diff) & 0xFFFF) as u16; // modulo 2^16
- let result = result << scan.point_transform;
- results[i][mcu_y * width + mcu_x] = result;
- }
- }
- }
- } else {
- for mcu_y in 0..height {
- for mcu_x in 0..width {
- for (i, _component) in components.iter().enumerate() {
- let diff = differences[i][mcu_y * width + mcu_x];
-
- // The following lines could be further optimized, e.g. moving the checks
- // and updates of the previous values into the prediction function or
- // iterating such that diagonals with mcu_x + mcu_y = const are computed at
- // the same time to exploit independent predictions in this case
- if mcu_x > 0 {
- ra[i] = results[i][mcu_y * frame.image_size.width as usize + mcu_x - 1];
- }
- if mcu_y > 0 {
- rb[i] =
- results[i][(mcu_y - 1) * frame.image_size.width as usize + mcu_x];
- if mcu_x > 0 {
- rc[i] = results[i]
- [(mcu_y - 1) * frame.image_size.width as usize + (mcu_x - 1)];
- }
- }
- let prediction = predict(
- ra[i] as i32,
- rb[i] as i32,
- rc[i] as i32,
- scan.predictor_selection,
- scan.point_transform,
- frame.precision,
- mcu_x,
- mcu_y,
- self.restart_interval > 0
- && mcus_left_until_restart == self.restart_interval - 1,
- );
- let result = ((prediction + diff) & 0xFFFF) as u16; // modulo 2^16
- results[i][mcu_y * width + mcu_x] = result << scan.point_transform;
- }
- }
- }
- }
-
- let mut marker = huffman.take_marker(&mut self.reader)?;
- while let Some(Marker::RST(_)) = marker {
- marker = self.read_marker().ok();
- }
- Ok((marker, results))
- }
-}
-
-/// H.1.2.1
-fn predict(
- ra: i32,
- rb: i32,
- rc: i32,
- predictor: Predictor,
- point_transform: u8,
- input_precision: u8,
- ix: usize,
- iy: usize,
- restart: bool,
-) -> i32 {
- if (ix == 0 && iy == 0) || restart {
- // start of first line or restart
- if input_precision > 1 + point_transform {
- 1 << (input_precision - point_transform - 1)
- } else {
- 0
- }
- } else if iy == 0 {
- // rest of first line
- ra
- } else if ix == 0 {
- // start of other line
- rb
- } else {
- // use predictor Table H.1
- match predictor {
- Predictor::NoPrediction => 0,
- Predictor::Ra => ra,
- Predictor::Rb => rb,
- Predictor::Rc => rc,
- Predictor::RaRbRc1 => ra + rb - rc,
- Predictor::RaRbRc2 => ra + ((rb - rc) >> 1),
- Predictor::RaRbRc3 => rb + ((ra - rc) >> 1),
- Predictor::RaRb => (ra + rb) / 2,
- }
- }
-}
-
-pub fn compute_image_lossless(frame: &FrameInfo, mut data: Vec<Vec<u16>>) -> Result<Vec<u8>> {
- if data.is_empty() || data.iter().any(Vec::is_empty) {
- return Err(Error::Format("not all components have data".to_owned()));
- }
- let output_size = frame.output_size;
- let components = &frame.components;
- let ncomp = components.len();
-
- if ncomp == 1 {
- let decoded = convert_to_u8(frame, data.remove(0));
- Ok(decoded)
- } else {
- let mut decoded: Vec<u16> =
- vec![0u16; ncomp * output_size.width as usize * output_size.height as usize];
- for (x, chunk) in decoded.chunks_mut(ncomp).enumerate() {
- for (i, (component_data, _)) in data.iter().zip(components.iter()).enumerate() {
- chunk[i] = component_data[x];
- }
- }
- let decoded = convert_to_u8(frame, decoded);
- Ok(decoded)
- }
-}
-
-fn convert_to_u8(frame: &FrameInfo, data: Vec<u16>) -> Vec<u8> {
- if frame.precision == 8 {
- data.iter().map(|x| *x as u8).collect()
- } else {
- // we output native endian, which is the standard for image-rs
- let ne_bytes: Vec<_> = data.iter().map(|x| x.to_ne_bytes()).collect();
- ne_bytes.concat()
- }
-}
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