FFmpeg
lossless_videodsp.h
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1 /*
2  * Lossless video DSP utils
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 
22 #ifndef AVCODEC_LOSSLESS_VIDEODSP_H
23 #define AVCODEC_LOSSLESS_VIDEODSP_H
24 
25 #include <stdint.h>
26 #include <stddef.h>
27 
28 #include "avcodec.h"
29 #include "libavutil/cpu.h"
30 
31 typedef struct LLVidDSPContext {
32  void (*add_bytes)(uint8_t *dst /* align 32 */, uint8_t *src /* align 32 */,
33  ptrdiff_t w);
34  void (*add_median_pred)(uint8_t *dst, const uint8_t *top,
35  const uint8_t *diff, ptrdiff_t w,
36  int *left, int *left_top);
37  int (*add_left_pred)(uint8_t *dst, const uint8_t *src,
38  ptrdiff_t w, int left);
39 
40  int (*add_left_pred_int16)(uint16_t *dst, const uint16_t *src,
41  unsigned mask, ptrdiff_t w, unsigned left);
42  void (*add_gradient_pred)(uint8_t *src /* align 32 */, const ptrdiff_t stride, const ptrdiff_t width);
44 
45 void ff_llviddsp_init(LLVidDSPContext *llviddsp);
48 
49 #endif //AVCODEC_LOSSLESS_VIDEODSP_H
stride
int stride
Definition: mace.c:144
w
uint8_t w
Definition: llviddspenc.c:38
ff_llviddsp_init_x86
void ff_llviddsp_init_x86(LLVidDSPContext *llviddsp)
Definition: lossless_videodsp_init.c:88
LLVidDSPContext::add_left_pred_int16
int(* add_left_pred_int16)(uint16_t *dst, const uint16_t *src, unsigned mask, ptrdiff_t w, unsigned left)
Definition: lossless_videodsp.h:40
ff_llviddsp_init
void ff_llviddsp_init(LLVidDSPContext *llviddsp)
Definition: lossless_videodsp.c:112
src
#define src
Definition: vp8dsp.c:254
LLVidDSPContext
Definition: lossless_videodsp.h:31
LLVidDSPContext::add_bytes
void(* add_bytes)(uint8_t *dst, uint8_t *src, ptrdiff_t w)
Definition: lossless_videodsp.h:32
mask
static const uint16_t mask[17]
Definition: lzw.c:38
width
#define width
cpu.h
ff_llviddsp_init_ppc
void ff_llviddsp_init_ppc(LLVidDSPContext *llviddsp)
Definition: lossless_videodsp_altivec.c:51
LLVidDSPContext::add_median_pred
void(* add_median_pred)(uint8_t *dst, const uint8_t *top, const uint8_t *diff, ptrdiff_t w, int *left, int *left_top)
Definition: lossless_videodsp.h:34
LLVidDSPContext::add_left_pred
int(* add_left_pred)(uint8_t *dst, const uint8_t *src, ptrdiff_t w, int left)
Definition: lossless_videodsp.h:37
uint8_t
uint8_t
Definition: audio_convert.c:194
avcodec.h
left
Tag MUST be and< 10hcoeff half pel interpolation filter coefficients, hcoeff[0] are the 2 middle coefficients[1] are the next outer ones and so on, resulting in a filter like:...eff[2], hcoeff[1], hcoeff[0], hcoeff[0], hcoeff[1], hcoeff[2] ... the sign of the coefficients is not explicitly stored but alternates after each coeff and coeff[0] is positive, so ...,+,-,+,-,+,+,-,+,-,+,... hcoeff[0] is not explicitly stored but found by subtracting the sum of all stored coefficients with signs from 32 hcoeff[0]=32 - hcoeff[1] - hcoeff[2] - ... a good choice for hcoeff and htaps is htaps=6 hcoeff={40,-10, 2} an alternative which requires more computations at both encoder and decoder side and may or may not be better is htaps=8 hcoeff={42,-14, 6,-2}ref_frames minimum of the number of available reference frames and max_ref_frames for example the first frame after a key frame always has ref_frames=1spatial_decomposition_type wavelet type 0 is a 9/7 symmetric compact integer wavelet 1 is a 5/3 symmetric compact integer wavelet others are reserved stored as delta from last, last is reset to 0 if always_reset||keyframeqlog quality(logarithmic quantizer scale) stored as delta from last, last is reset to 0 if always_reset||keyframemv_scale stored as delta from last, last is reset to 0 if always_reset||keyframe FIXME check that everything works fine if this changes between framesqbias dequantization bias stored as delta from last, last is reset to 0 if always_reset||keyframeblock_max_depth maximum depth of the block tree stored as delta from last, last is reset to 0 if always_reset||keyframequant_table quantization tableHighlevel bitstream structure:==============================--------------------------------------------|Header|--------------------------------------------|------------------------------------|||Block0||||split?||||yes no||||......... intra?||||:Block01 :yes no||||:Block02 :....... ..........||||:Block03 ::y DC ::ref index:||||:Block04 ::cb DC ::motion x :||||......... :cr DC ::motion y :||||....... ..........|||------------------------------------||------------------------------------|||Block1|||...|--------------------------------------------|------------ ------------ ------------|||Y subbands||Cb subbands||Cr subbands||||--- ---||--- ---||--- ---|||||LL0||HL0||||LL0||HL0||||LL0||HL0|||||--- ---||--- ---||--- ---||||--- ---||--- ---||--- ---|||||LH0||HH0||||LH0||HH0||||LH0||HH0|||||--- ---||--- ---||--- ---||||--- ---||--- ---||--- ---|||||HL1||LH1||||HL1||LH1||||HL1||LH1|||||--- ---||--- ---||--- ---||||--- ---||--- ---||--- ---|||||HH1||HL2||||HH1||HL2||||HH1||HL2|||||...||...||...|||------------ ------------ ------------|--------------------------------------------Decoding process:=================------------|||Subbands|------------||||------------|Intra DC||||LL0 subband prediction ------------|\ Dequantization ------------------- \||Reference frames|\ IDWT|------- -------|Motion \|||Frame 0||Frame 1||Compensation . OBMC v -------|------- -------|--------------. \------> Frame n output Frame Frame<----------------------------------/|...|------------------- Range Coder:============Binary Range Coder:------------------- The implemented range coder is an adapted version based upon "Range encoding: an algorithm for removing redundancy from a digitised message." by G. N. N. Martin. The symbols encoded by the Snow range coder are bits(0|1). The associated probabilities are not fix but change depending on the symbol mix seen so far. bit seen|new state ---------+----------------------------------------------- 0|256 - state_transition_table[256 - old_state];1|state_transition_table[old_state];state_transition_table={ 0, 0, 0, 0, 0, 0, 0, 0, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 190, 191, 192, 194, 194, 195, 196, 197, 198, 199, 200, 201, 202, 202, 204, 205, 206, 207, 208, 209, 209, 210, 211, 212, 213, 215, 215, 216, 217, 218, 219, 220, 220, 222, 223, 224, 225, 226, 227, 227, 229, 229, 230, 231, 232, 234, 234, 235, 236, 237, 238, 239, 240, 241, 242, 243, 244, 245, 246, 247, 248, 248, 0, 0, 0, 0, 0, 0, 0};FIXME Range Coding of integers:------------------------- FIXME Neighboring Blocks:===================left and top are set to the respective blocks unless they are outside of the image in which case they are set to the Null block top-left is set to the top left block unless it is outside of the image in which case it is set to the left block if this block has no larger parent block or it is at the left side of its parent block and the top right block is not outside of the image then the top right block is used for top-right else the top-left block is used Null block y, cb, cr are 128 level, ref, mx and my are 0 Motion Vector Prediction:=========================1. the motion vectors of all the neighboring blocks are scaled to compensate for the difference of reference frames scaled_mv=(mv *(256 *(current_reference+1)/(mv.reference+1))+128)> the median of the scaled left
Definition: snow.txt:386
diff
static av_always_inline int diff(const uint32_t a, const uint32_t b)
Definition: vf_palettegen.c:136
LLVidDSPContext::add_gradient_pred
void(* add_gradient_pred)(uint8_t *src, const ptrdiff_t stride, const ptrdiff_t width)
Definition: lossless_videodsp.h:42
int
int
Definition: ffmpeg_filter.c:191