FFmpeg
venc_data_dump.c
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1 /*
2  * This file is part of FFmpeg.
3  *
4  * FFmpeg is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
7  * version 2.1 of the License, or (at your option) any later version.
8  *
9  * FFmpeg is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * Lesser General Public License for more details.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with FFmpeg; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17  */
18 
19 #include <stdio.h>
20 #include <stdint.h>
21 #include <stdlib.h>
22 
23 #include "decode_simple.h"
24 
25 #include "libavutil/common.h"
26 #include "libavutil/dict.h"
27 #include "libavutil/error.h"
29 
30 #include "libavformat/avformat.h"
31 
32 #include "libavcodec/avcodec.h"
33 
35 {
36  AVFrameSideData *sd;
37 
38  if (!frame)
39  return 0;
40 
41  fprintf(stdout, "frame %d\n", dc->decoder->frame_number - 1);
42 
44  if (sd) {
46 
47  fprintf(stdout, "AVVideoEncParams %d\n", par->type);
48  fprintf(stdout, "qp %d\n", par->qp);
49  for (int i = 0; i < FF_ARRAY_ELEMS(par->delta_qp); i++)
50  for (int j = 0; j < FF_ARRAY_ELEMS(par->delta_qp[i]); j++) {
51  if (par->delta_qp[i][j])
52  fprintf(stdout, "delta_qp[%d][%d] %"PRId32"\n", i, j, par->delta_qp[i][j]);
53  }
54 
55  if (par->nb_blocks) {
56  fprintf(stdout, "nb_blocks %d\n", par->nb_blocks);
57  for (int i = 0; i < par->nb_blocks; i++) {
59 
60  fprintf(stdout, "block %d %d:%d %dx%d %"PRId32"\n",
61  i, b->src_x, b->src_y, b->w, b->h, b->delta_qp);
62  }
63  }
64  }
65 
66  return 0;
67 }
68 
69 int main(int argc, char **argv)
70 {
72 
73  unsigned int stream_idx, max_frames;
74  const char *filename, *thread_type = NULL, *nb_threads = NULL;
75  int ret = 0;
76 
77  if (argc <= 3) {
78  fprintf(stderr, "Usage: %s <input file> <stream index> <max frame count> [<thread count> <thread type>]\n", argv[0]);
79  return 0;
80  }
81 
82  filename = argv[1];
83  stream_idx = strtol(argv[2], NULL, 0);
84  max_frames = strtol(argv[3], NULL, 0);
85  if (argc > 5) {
86  nb_threads = argv[4];
87  thread_type = argv[5];
88  }
89 
90  ret = ds_open(&dc, filename, stream_idx);
91  if (ret < 0)
92  goto finish;
93 
94  dc.process_frame = process_frame;
95  dc.max_frames = max_frames;
96 
97  ret = av_dict_set(&dc.decoder_opts, "threads", nb_threads, 0);
98  ret |= av_dict_set(&dc.decoder_opts, "thread_type", thread_type, 0);
99  ret |= av_dict_set(&dc.decoder_opts, "export_side_data", "venc_params", 0);
100 
101  if (ret < 0)
102  goto finish;
103 
104  ret = ds_run(&dc);
105 
106 finish:
107  ds_free(&dc);
108  return ret;
109 }
AVVideoEncParams::qp
int32_t qp
Base quantisation parameter for the frame.
Definition: video_enc_params.h:103
av_frame_get_side_data
AVFrameSideData * av_frame_get_side_data(const AVFrame *frame, enum AVFrameSideDataType type)
Definition: frame.c:617
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:303
b
#define b
Definition: input.c:40
ds_open
int ds_open(DecodeContext *dc, const char *url, int stream_idx)
Definition: decode_simple.c:119
finish
static void finish(void)
Definition: movenc.c:342
AVVideoEncParams::delta_qp
int32_t delta_qp[4][2]
Quantisation parameter offset from the base (per-frame) qp for a given plane (first index) and AC/DC ...
Definition: video_enc_params.h:109
ds_run
int ds_run(DecodeContext *dc)
Definition: decode_simple.c:65
AVVideoEncParams
Video encoding parameters for a given frame.
Definition: video_enc_params.h:73
FF_ARRAY_ELEMS
#define FF_ARRAY_ELEMS(a)
Definition: sinewin_tablegen.c:29
AVVideoEncParams::type
enum AVVideoEncParamsType type
Type of the parameters (the codec they are used with).
Definition: video_enc_params.h:95
NULL
#define NULL
Definition: coverity.c:32
error.h
dc
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
AVFrameSideData::data
uint8_t * data
Definition: frame.h:211
AVVideoEncParams::nb_blocks
unsigned int nb_blocks
Number of blocks in the array.
Definition: video_enc_params.h:81
i
int i
Definition: input.c:406
common.h
AVVideoBlockParams
Data structure for storing block-level encoding information.
Definition: video_enc_params.h:120
process_frame
static int process_frame(DecodeContext *dc, AVFrame *frame)
Definition: venc_data_dump.c:34
avcodec.h
ret
ret
Definition: filter_design.txt:187
frame
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:264
avformat.h
dict.h
AV_FRAME_DATA_VIDEO_ENC_PARAMS
@ AV_FRAME_DATA_VIDEO_ENC_PARAMS
Encoding parameters for a video frame, as described by AVVideoEncParams.
Definition: frame.h:169
AVFrameSideData
Structure to hold side data for an AVFrame.
Definition: frame.h:209
av_dict_set
int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags)
Set the given entry in *pm, overwriting an existing entry.
Definition: dict.c:70
ds_free
void ds_free(DecodeContext *dc)
Definition: decode_simple.c:108
av_video_enc_params_block
static av_always_inline AVVideoBlockParams * av_video_enc_params_block(AVVideoEncParams *par, unsigned int idx)
Definition: video_enc_params.h:143
decode_simple.h
main
int main(int argc, char **argv)
Definition: venc_data_dump.c:69
DecodeContext
Definition: decode_simple.h:33
video_enc_params.h