FFmpeg
vp8dsp.h
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1 /*
2  * Copyright (C) 2010 David Conrad
3  * Copyright (C) 2010 Ronald S. Bultje
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * VP8 compatible video decoder
25  */
26 
27 #ifndef AVCODEC_VP8DSP_H
28 #define AVCODEC_VP8DSP_H
29 
30 #include <stddef.h>
31 #include <stdint.h>
32 
33 typedef void (*vp8_mc_func)(uint8_t *dst /* align 8 */, ptrdiff_t dstStride,
34  uint8_t *src /* align 1 */, ptrdiff_t srcStride,
35  int h, int x, int y);
36 
37 typedef struct VP8DSPContext {
38  void (*vp8_luma_dc_wht)(int16_t block[4][4][16], int16_t dc[16]);
39  void (*vp8_luma_dc_wht_dc)(int16_t block[4][4][16], int16_t dc[16]);
40  void (*vp8_idct_add)(uint8_t *dst, int16_t block[16], ptrdiff_t stride);
41  void (*vp8_idct_dc_add)(uint8_t *dst, int16_t block[16], ptrdiff_t stride);
42  void (*vp8_idct_dc_add4y)(uint8_t *dst, int16_t block[4][16],
43  ptrdiff_t stride);
44  void (*vp8_idct_dc_add4uv)(uint8_t *dst, int16_t block[4][16],
45  ptrdiff_t stride);
46 
47  // loop filter applied to edges between macroblocks
49  int flim_E, int flim_I, int hev_thresh);
51  int flim_E, int flim_I, int hev_thresh);
52  void (*vp8_v_loop_filter8uv)(uint8_t *dstU, uint8_t *dstV, ptrdiff_t stride,
53  int flim_E, int flim_I, int hev_thresh);
54  void (*vp8_h_loop_filter8uv)(uint8_t *dstU, uint8_t *dstV, ptrdiff_t stride,
55  int flim_E, int flim_I, int hev_thresh);
56 
57  // loop filter applied to inner macroblock edges
59  int flim_E, int flim_I, int hev_thresh);
61  int flim_E, int flim_I, int hev_thresh);
63  ptrdiff_t stride,
64  int flim_E, int flim_I, int hev_thresh);
66  ptrdiff_t stride,
67  int flim_E, int flim_I, int hev_thresh);
68 
69  void (*vp8_v_loop_filter_simple)(uint8_t *dst, ptrdiff_t stride, int flim);
70  void (*vp8_h_loop_filter_simple)(uint8_t *dst, ptrdiff_t stride, int flim);
71 
72  /**
73  * first dimension: 4-log2(width)
74  * second dimension: 0 if no vertical interpolation is needed;
75  * 1 4-tap vertical interpolation filter (my & 1)
76  * 2 6-tap vertical interpolation filter (!(my & 1))
77  * third dimension: same as second dimension, for horizontal interpolation
78  * so something like put_vp8_epel_pixels_tab[4-log2(width)][2*!!my-(my&1)][2*!!mx-(mx&1)](..., mx, my)
79  */
83 
84 void ff_put_vp8_pixels16_c(uint8_t *dst, uint8_t *src, ptrdiff_t stride,
85  int h, int x, int y);
86 void ff_put_vp8_pixels8_c(uint8_t *dst, uint8_t *src, ptrdiff_t stride,
87  int h, int x, int y);
88 void ff_put_vp8_pixels4_c(uint8_t *dst, uint8_t *src, ptrdiff_t stride,
89  int h, int x, int y);
90 
92 
98 
104 
105 #define IS_VP7 1
106 #define IS_VP8 0
107 
108 #endif /* AVCODEC_VP8DSP_H */
void(* vp8_idct_dc_add)(uint8_t *dst, int16_t block[16], ptrdiff_t stride)
Definition: vp8dsp.h:41
void ff_vp7dsp_init(VP8DSPContext *c)
void ff_vp78dsp_init(VP8DSPContext *c)
Definition: vp8dsp.c:666
void(* vp8_idct_dc_add4y)(uint8_t *dst, int16_t block[4][16], ptrdiff_t stride)
Definition: vp8dsp.h:42
void ff_put_vp8_pixels4_c(uint8_t *dst, uint8_t *src, ptrdiff_t stride, int h, int x, int y)
vp8_mc_func put_vp8_bilinear_pixels_tab[3][3][3]
Definition: vp8dsp.h:81
void(* vp8_v_loop_filter8uv_inner)(uint8_t *dstU, uint8_t *dstV, ptrdiff_t stride, int flim_E, int flim_I, int hev_thresh)
Definition: vp8dsp.h:62
void ff_put_vp8_pixels16_c(uint8_t *dst, uint8_t *src, ptrdiff_t stride, int h, int x, int y)
void ff_vp8dsp_init_aarch64(VP8DSPContext *c)
#define src
Definition: vp8dsp.c:254
vp8_mc_func put_vp8_epel_pixels_tab[3][3][3]
first dimension: 4-log2(width) second dimension: 0 if no vertical interpolation is needed; 1 4-tap ve...
Definition: vp8dsp.h:80
void ff_vp78dsp_init_aarch64(VP8DSPContext *c)
The exact code depends on how similar the blocks are and how related they are to the block
uint8_t
void(* vp8_luma_dc_wht_dc)(int16_t block[4][4][16], int16_t dc[16])
Definition: vp8dsp.h:39
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
void(* vp8_idct_dc_add4uv)(uint8_t *dst, int16_t block[4][16], ptrdiff_t stride)
Definition: vp8dsp.h:44
void(* vp8_v_loop_filter8uv)(uint8_t *dstU, uint8_t *dstV, ptrdiff_t stride, int flim_E, int flim_I, int hev_thresh)
Definition: vp8dsp.h:52
void(* vp8_idct_add)(uint8_t *dst, int16_t block[16], ptrdiff_t stride)
Definition: vp8dsp.h:40
void ff_vp8dsp_init_mips(VP8DSPContext *c)
void ff_vp78dsp_init_ppc(VP8DSPContext *c)
typedef void(APIENTRY *FF_PFNGLACTIVETEXTUREPROC)(GLenum texture)
void(* vp8_h_loop_filter8uv_inner)(uint8_t *dstU, uint8_t *dstV, ptrdiff_t stride, int flim_E, int flim_I, int hev_thresh)
Definition: vp8dsp.h:65
void(* vp8_mc_func)(uint8_t *dst, ptrdiff_t dstStride, uint8_t *src, ptrdiff_t srcStride, int h, int x, int y)
Definition: vp8dsp.h:33
void(* vp8_v_loop_filter16y)(uint8_t *dst, ptrdiff_t stride, int flim_E, int flim_I, int hev_thresh)
Definition: vp8dsp.h:48
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 top and top right vectors is used as motion vector prediction the used motion vector is the sum of the predictor and(mvx_diff, mvy_diff)*mv_scale Intra DC Prediction block[y][x] dc[1]
Definition: snow.txt:400
void ff_vp78dsp_init_arm(VP8DSPContext *c)
void ff_vp78dsp_init_x86(VP8DSPContext *c)
Definition: vp8dsp_init.c:319
void(* vp8_h_loop_filter8uv)(uint8_t *dstU, uint8_t *dstV, ptrdiff_t stride, int flim_E, int flim_I, int hev_thresh)
Definition: vp8dsp.h:54
void ff_vp8dsp_init_x86(VP8DSPContext *c)
Definition: vp8dsp_init.c:369
void ff_put_vp8_pixels8_c(uint8_t *dst, uint8_t *src, ptrdiff_t stride, int h, int x, int y)
void(* vp8_h_loop_filter16y_inner)(uint8_t *dst, ptrdiff_t stride, int flim_E, int flim_I, int hev_thresh)
Definition: vp8dsp.h:60
void(* vp8_luma_dc_wht)(int16_t block[4][4][16], int16_t dc[16])
Definition: vp8dsp.h:38
void(* vp8_v_loop_filter_simple)(uint8_t *dst, ptrdiff_t stride, int flim)
Definition: vp8dsp.h:69
void(* vp8_h_loop_filter_simple)(uint8_t *dst, ptrdiff_t stride, int flim)
Definition: vp8dsp.h:70
GLint GLenum GLboolean GLsizei stride
Definition: opengl_enc.c:104
void(* vp8_v_loop_filter16y_inner)(uint8_t *dst, ptrdiff_t stride, int flim_E, int flim_I, int hev_thresh)
Definition: vp8dsp.h:58
void ff_vp8dsp_init_arm(VP8DSPContext *c)
#define stride
void(* vp8_h_loop_filter16y)(uint8_t *dst, ptrdiff_t stride, int flim_E, int flim_I, int hev_thresh)
Definition: vp8dsp.h:50
void ff_vp8dsp_init(VP8DSPContext *c)