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Diffstat (limited to 'vendor/image/src/codecs/jpeg/transform.rs')
| -rw-r--r-- | vendor/image/src/codecs/jpeg/transform.rs | 196 |
1 files changed, 0 insertions, 196 deletions
diff --git a/vendor/image/src/codecs/jpeg/transform.rs b/vendor/image/src/codecs/jpeg/transform.rs deleted file mode 100644 index 1ca01a9..0000000 --- a/vendor/image/src/codecs/jpeg/transform.rs +++ /dev/null @@ -1,196 +0,0 @@ -/* -fdct is a Rust translation of jfdctint.c from the -Independent JPEG Group's libjpeg version 9a -obtained from http://www.ijg.org/files/jpegsr9a.zip -It comes with the following conditions of distribution and use: - - In plain English: - - 1. We don't promise that this software works. (But if you find any bugs, - please let us know!) - 2. You can use this software for whatever you want. You don't have to pay us. - 3. You may not pretend that you wrote this software. If you use it in a - program, you must acknowledge somewhere in your documentation that - you've used the IJG code. - - In legalese: - - The authors make NO WARRANTY or representation, either express or implied, - with respect to this software, its quality, accuracy, merchantability, or - fitness for a particular purpose. This software is provided "AS IS", and you, - its user, assume the entire risk as to its quality and accuracy. - - This software is copyright (C) 1991-2014, Thomas G. Lane, Guido Vollbeding. - All Rights Reserved except as specified below. - - Permission is hereby granted to use, copy, modify, and distribute this - software (or portions thereof) for any purpose, without fee, subject to these - conditions: - (1) If any part of the source code for this software is distributed, then this - README file must be included, with this copyright and no-warranty notice - unaltered; and any additions, deletions, or changes to the original files - must be clearly indicated in accompanying documentation. - (2) If only executable code is distributed, then the accompanying - documentation must state that "this software is based in part on the work of - the Independent JPEG Group". - (3) Permission for use of this software is granted only if the user accepts - full responsibility for any undesirable consequences; the authors accept - NO LIABILITY for damages of any kind. - - These conditions apply to any software derived from or based on the IJG code, - not just to the unmodified library. If you use our work, you ought to - acknowledge us. - - Permission is NOT granted for the use of any IJG author's name or company name - in advertising or publicity relating to this software or products derived from - it. This software may be referred to only as "the Independent JPEG Group's - software". - - We specifically permit and encourage the use of this software as the basis of - commercial products, provided that all warranty or liability claims are - assumed by the product vendor. -*/ - -static CONST_BITS: i32 = 13; -static PASS1_BITS: i32 = 2; - -static FIX_0_298631336: i32 = 2446; -static FIX_0_390180644: i32 = 3196; -static FIX_0_541196100: i32 = 4433; -static FIX_0_765366865: i32 = 6270; -static FIX_0_899976223: i32 = 7373; -static FIX_1_175875602: i32 = 9633; -static FIX_1_501321110: i32 = 12_299; -static FIX_1_847759065: i32 = 15_137; -static FIX_1_961570560: i32 = 16_069; -static FIX_2_053119869: i32 = 16_819; -static FIX_2_562915447: i32 = 20_995; -static FIX_3_072711026: i32 = 25_172; - -pub(crate) fn fdct(samples: &[u8; 64], coeffs: &mut [i32; 64]) { - // Pass 1: process rows. - // Results are scaled by sqrt(8) compared to a true DCT - // furthermore we scale the results by 2**PASS1_BITS - for y in 0usize..8 { - let y0 = y * 8; - - // Even part - let t0 = i32::from(samples[y0]) + i32::from(samples[y0 + 7]); - let t1 = i32::from(samples[y0 + 1]) + i32::from(samples[y0 + 6]); - let t2 = i32::from(samples[y0 + 2]) + i32::from(samples[y0 + 5]); - let t3 = i32::from(samples[y0 + 3]) + i32::from(samples[y0 + 4]); - - let t10 = t0 + t3; - let t12 = t0 - t3; - let t11 = t1 + t2; - let t13 = t1 - t2; - - let t0 = i32::from(samples[y0]) - i32::from(samples[y0 + 7]); - let t1 = i32::from(samples[y0 + 1]) - i32::from(samples[y0 + 6]); - let t2 = i32::from(samples[y0 + 2]) - i32::from(samples[y0 + 5]); - let t3 = i32::from(samples[y0 + 3]) - i32::from(samples[y0 + 4]); - - // Apply unsigned -> signed conversion - coeffs[y0] = (t10 + t11 - 8 * 128) << PASS1_BITS as usize; - coeffs[y0 + 4] = (t10 - t11) << PASS1_BITS as usize; - - let mut z1 = (t12 + t13) * FIX_0_541196100; - // Add fudge factor here for final descale - z1 += 1 << (CONST_BITS - PASS1_BITS - 1) as usize; - - coeffs[y0 + 2] = (z1 + t12 * FIX_0_765366865) >> (CONST_BITS - PASS1_BITS) as usize; - coeffs[y0 + 6] = (z1 - t13 * FIX_1_847759065) >> (CONST_BITS - PASS1_BITS) as usize; - - // Odd part - let t12 = t0 + t2; - let t13 = t1 + t3; - - let mut z1 = (t12 + t13) * FIX_1_175875602; - // Add fudge factor here for final descale - z1 += 1 << (CONST_BITS - PASS1_BITS - 1) as usize; - - let mut t12 = t12 * (-FIX_0_390180644); - let mut t13 = t13 * (-FIX_1_961570560); - t12 += z1; - t13 += z1; - - let z1 = (t0 + t3) * (-FIX_0_899976223); - let mut t0 = t0 * FIX_1_501321110; - let mut t3 = t3 * FIX_0_298631336; - t0 += z1 + t12; - t3 += z1 + t13; - - let z1 = (t1 + t2) * (-FIX_2_562915447); - let mut t1 = t1 * FIX_3_072711026; - let mut t2 = t2 * FIX_2_053119869; - t1 += z1 + t13; - t2 += z1 + t12; - - coeffs[y0 + 1] = t0 >> (CONST_BITS - PASS1_BITS) as usize; - coeffs[y0 + 3] = t1 >> (CONST_BITS - PASS1_BITS) as usize; - coeffs[y0 + 5] = t2 >> (CONST_BITS - PASS1_BITS) as usize; - coeffs[y0 + 7] = t3 >> (CONST_BITS - PASS1_BITS) as usize; - } - - // Pass 2: process columns - // We remove the PASS1_BITS scaling but leave the results scaled up an - // overall factor of 8 - for x in (0usize..8).rev() { - // Even part - let t0 = coeffs[x] + coeffs[x + 8 * 7]; - let t1 = coeffs[x + 8] + coeffs[x + 8 * 6]; - let t2 = coeffs[x + 8 * 2] + coeffs[x + 8 * 5]; - let t3 = coeffs[x + 8 * 3] + coeffs[x + 8 * 4]; - - // Add fudge factor here for final descale - let t10 = t0 + t3 + (1 << (PASS1_BITS - 1) as usize); - let t12 = t0 - t3; - let t11 = t1 + t2; - let t13 = t1 - t2; - - let t0 = coeffs[x] - coeffs[x + 8 * 7]; - let t1 = coeffs[x + 8] - coeffs[x + 8 * 6]; - let t2 = coeffs[x + 8 * 2] - coeffs[x + 8 * 5]; - let t3 = coeffs[x + 8 * 3] - coeffs[x + 8 * 4]; - - coeffs[x] = (t10 + t11) >> PASS1_BITS as usize; - coeffs[x + 8 * 4] = (t10 - t11) >> PASS1_BITS as usize; - - let mut z1 = (t12 + t13) * FIX_0_541196100; - // Add fudge factor here for final descale - z1 += 1 << (CONST_BITS + PASS1_BITS - 1) as usize; - - coeffs[x + 8 * 2] = (z1 + t12 * FIX_0_765366865) >> (CONST_BITS + PASS1_BITS) as usize; - coeffs[x + 8 * 6] = (z1 - t13 * FIX_1_847759065) >> (CONST_BITS + PASS1_BITS) as usize; - - // Odd part - let t12 = t0 + t2; - let t13 = t1 + t3; - - let mut z1 = (t12 + t13) * FIX_1_175875602; - // Add fudge factor here for final descale - z1 += 1 << (CONST_BITS - PASS1_BITS - 1) as usize; - - let mut t12 = t12 * (-FIX_0_390180644); - let mut t13 = t13 * (-FIX_1_961570560); - t12 += z1; - t13 += z1; - - let z1 = (t0 + t3) * (-FIX_0_899976223); - let mut t0 = t0 * FIX_1_501321110; - let mut t3 = t3 * FIX_0_298631336; - t0 += z1 + t12; - t3 += z1 + t13; - - let z1 = (t1 + t2) * (-FIX_2_562915447); - let mut t1 = t1 * FIX_3_072711026; - let mut t2 = t2 * FIX_2_053119869; - t1 += z1 + t13; - t2 += z1 + t12; - - coeffs[x + 8] = t0 >> (CONST_BITS + PASS1_BITS) as usize; - coeffs[x + 8 * 3] = t1 >> (CONST_BITS + PASS1_BITS) as usize; - coeffs[x + 8 * 5] = t2 >> (CONST_BITS + PASS1_BITS) as usize; - coeffs[x + 8 * 7] = t3 >> (CONST_BITS + PASS1_BITS) as usize; - } -} |