FFmpeg
h263.h
Go to the documentation of this file.
1 /*
2  * H.263 internal header
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 #ifndef AVCODEC_H263_H
21 #define AVCODEC_H263_H
22 
23 #include <stdint.h>
24 #include "libavutil/rational.h"
25 #include "get_bits.h"
26 #include "mpegvideo.h"
27 #include "h263data.h"
28 #include "rl.h"
29 
30 #define FF_ASPECT_EXTENDED 15
31 #define INT_BIT (CHAR_BIT * sizeof(int))
32 
33 // The defines below define the number of bits that are read at once for
34 // reading vlc values. Changing these may improve speed and data cache needs
35 // be aware though that decreasing them may need the number of stages that is
36 // passed to get_vlc* to be increased.
37 #define H263_MV_VLC_BITS 9
38 #define INTRA_MCBPC_VLC_BITS 6
39 #define INTER_MCBPC_VLC_BITS 7
40 #define CBPY_VLC_BITS 6
41 #define TEX_VLC_BITS 9
42 
43 #define H263_GOB_HEIGHT(h) ((h) <= 400 ? 1 : (h) <= 800 ? 2 : 4)
44 
47 extern VLC ff_h263_cbpy_vlc;
48 extern VLC ff_h263_mv_vlc;
49 
51 
52 
53 int ff_h263_decode_motion(MpegEncContext * s, int pred, int f_code);
57  void *data, int *got_frame,
58  AVPacket *avpkt);
61  int16_t block[6][64],
62  int motion_x, int motion_y);
63 void ff_h263_encode_picture_header(MpegEncContext *s, int picture_number);
64 void ff_h263_encode_gob_header(MpegEncContext * s, int mb_line);
65 int16_t *ff_h263_pred_motion(MpegEncContext * s, int block, int dir,
66  int *px, int *py);
68 void ff_h263_decode_init_vlc(void);
69 void ff_h263_init_rl_inter(void);
77 int ff_h263_pred_dc(MpegEncContext * s, int n, int16_t **dc_val_ptr);
78 void ff_h263_pred_acdc(MpegEncContext * s, int16_t *block, int n);
79 
80 
81 /**
82  * Print picture info if FF_DEBUG_PICT_INFO is set.
83  */
85 
88  int16_t block[6][64]);
89 
90 /**
91  * Return the value of the 3-bit "source format" syntax element.
92  * This represents some standard picture dimensions or indicates that
93  * width&height are explicitly stored later.
94  */
96 
99 void ff_h263_encode_motion(PutBitContext *pb, int val, int f_code);
100 
101 
102 static inline int h263_get_motion_length(int val, int f_code){
103  int l, bit_size, code;
104 
105  if (val == 0) {
106  return ff_mvtab[0][1];
107  } else {
108  bit_size = f_code - 1;
109  /* modulo encoding */
110  l= INT_BIT - 6 - bit_size;
111  val = (val<<l)>>l;
112  val--;
113  code = (val >> bit_size) + 1;
114 
115  return ff_mvtab[code][1] + 1 + bit_size;
116  }
117 }
118 
119 static inline void ff_h263_encode_motion_vector(MpegEncContext * s, int x, int y, int f_code){
120  if (s->avctx->flags2 & AV_CODEC_FLAG2_NO_OUTPUT) {
121  skip_put_bits(&s->pb,
122  h263_get_motion_length(x, f_code)
123  +h263_get_motion_length(y, f_code));
124  }else{
125  ff_h263_encode_motion(&s->pb, x, f_code);
126  ff_h263_encode_motion(&s->pb, y, f_code);
127  }
128 }
129 
130 static inline int get_p_cbp(MpegEncContext * s,
131  int16_t block[6][64],
132  int motion_x, int motion_y){
133  int cbp, i;
134 
135  if (s->mpv_flags & FF_MPV_FLAG_CBP_RD) {
136  int best_cbpy_score= INT_MAX;
137  int best_cbpc_score= INT_MAX;
138  int cbpc = (-1), cbpy= (-1);
139  const int offset= (s->mv_type==MV_TYPE_16X16 ? 0 : 16) + (s->dquant ? 8 : 0);
140  const int lambda= s->lambda2 >> (FF_LAMBDA_SHIFT - 6);
141 
142  for(i=0; i<4; i++){
143  int score= ff_h263_inter_MCBPC_bits[i + offset] * lambda;
144  if(i&1) score += s->coded_score[5];
145  if(i&2) score += s->coded_score[4];
146 
147  if(score < best_cbpc_score){
148  best_cbpc_score= score;
149  cbpc= i;
150  }
151  }
152 
153  for(i=0; i<16; i++){
154  int score= ff_h263_cbpy_tab[i ^ 0xF][1] * lambda;
155  if(i&1) score += s->coded_score[3];
156  if(i&2) score += s->coded_score[2];
157  if(i&4) score += s->coded_score[1];
158  if(i&8) score += s->coded_score[0];
159 
160  if(score < best_cbpy_score){
161  best_cbpy_score= score;
162  cbpy= i;
163  }
164  }
165  cbp= cbpc + 4*cbpy;
166  if ((motion_x | motion_y | s->dquant) == 0 && s->mv_type==MV_TYPE_16X16){
167  if(best_cbpy_score + best_cbpc_score + 2*lambda >= 0)
168  cbp= 0;
169  }
170 
171  for (i = 0; i < 6; i++) {
172  if (s->block_last_index[i] >= 0 && ((cbp >> (5 - i))&1)==0 ){
173  s->block_last_index[i]= -1;
174  s->bdsp.clear_block(s->block[i]);
175  }
176  }
177  }else{
178  cbp= 0;
179  for (i = 0; i < 6; i++) {
180  if (s->block_last_index[i] >= 0)
181  cbp |= 1 << (5 - i);
182  }
183  }
184  return cbp;
185 }
186 
187 #endif /* AVCODEC_H263_H */
MV_TYPE_16X16
#define MV_TYPE_16X16
1 vector for the whole mb
Definition: mpegvideo.h:256
h263data.h
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
rational.h
ff_init_qscale_tab
void ff_init_qscale_tab(MpegEncContext *s)
init s->current_picture.qscale_table from s->lambda_table
Definition: mpegvideo_enc.c:234
av_const
#define av_const
Definition: attributes.h:84
data
const char data[16]
Definition: mxf.c:143
ff_h263_decode_mba
int ff_h263_decode_mba(MpegEncContext *s)
Definition: ituh263dec.c:138
h263_get_motion_length
static int h263_get_motion_length(int val, int f_code)
Definition: h263.h:102
mpegvideo.h
FF_LAMBDA_SHIFT
#define FF_LAMBDA_SHIFT
Definition: avutil.h:225
ff_h263_intra_MCBPC_vlc
VLC ff_h263_intra_MCBPC_vlc
Definition: ituh263dec.c:98
val
static double val(void *priv, double ch)
Definition: aeval.c:76
AV_CODEC_FLAG2_NO_OUTPUT
#define AV_CODEC_FLAG2_NO_OUTPUT
Skip bitstream encoding.
Definition: avcodec.h:291
ff_h263_pred_dc
int ff_h263_pred_dc(MpegEncContext *s, int n, int16_t **dc_val_ptr)
Definition: h263.c:105
h263_get_picture_format
int av_const h263_get_picture_format(int width, int height)
Return the value of the 3-bit "source format" syntax element.
ff_h263_decode_init_vlc
void ff_h263_decode_init_vlc(void)
Definition: ituh263dec.c:108
ff_h263_encode_init
void ff_h263_encode_init(MpegEncContext *s)
Definition: ituh263enc.c:771
width
#define width
s
#define s(width, name)
Definition: cbs_vp9.c:257
skip_put_bits
static void skip_put_bits(PutBitContext *s, int n)
Skip the given number of bits.
Definition: put_bits.h:391
get_p_cbp
static int get_p_cbp(MpegEncContext *s, int16_t block[6][64], int motion_x, int motion_y)
Definition: h263.h:130
get_bits.h
ff_h263_encode_picture_header
void ff_h263_encode_picture_header(MpegEncContext *s, int picture_number)
Definition: ituh263enc.c:104
ff_h263_encode_gob_header
void ff_h263_encode_gob_header(MpegEncContext *s, int mb_line)
Encode a group of blocks header.
Definition: ituh263enc.c:241
PutBitContext
Definition: put_bits.h:49
ff_h263_init_rl_inter
void ff_h263_init_rl_inter(void)
Definition: h263.c:47
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
ff_h263_hwaccel_pixfmt_list_420
enum AVPixelFormat ff_h263_hwaccel_pixfmt_list_420[]
Definition: h263dec.c:736
ff_h263_update_motion_val
void ff_h263_update_motion_val(MpegEncContext *s)
Definition: h263.c:53
ff_h263_show_pict_info
void ff_h263_show_pict_info(MpegEncContext *s)
Print picture info if FF_DEBUG_PICT_INFO is set.
Definition: ituh263dec.c:76
ff_clean_h263_qscales
void ff_clean_h263_qscales(MpegEncContext *s)
modify qscale so that encoding is actually possible in H.263 (limit difference to -2....
Definition: ituh263enc.c:267
ff_h263_encode_mba
void ff_h263_encode_mba(MpegEncContext *s)
Definition: ituh263enc.c:826
ff_intel_h263_decode_picture_header
int ff_intel_h263_decode_picture_header(MpegEncContext *s)
Definition: intelh263dec.c:27
ff_h263_loop_filter
void ff_h263_loop_filter(MpegEncContext *s)
Definition: h263.c:146
ff_h263_decode_motion
int ff_h263_decode_motion(MpegEncContext *s, int pred, int f_code)
Definition: ituh263dec.c:269
ff_h263_resync
int ff_h263_resync(MpegEncContext *s)
Decode the group of blocks / video packet header / slice header (MPEG-4 Studio).
Definition: ituh263dec.c:212
ff_h263_cbpy_tab
const uint8_t ff_h263_cbpy_tab[16][2]
Definition: h263data.c:82
height
#define height
offset
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf offset
Definition: writing_filters.txt:86
ff_h263_inter_MCBPC_bits
const uint8_t ff_h263_inter_MCBPC_bits[28]
Definition: h263data.c:47
ff_h263_mv_vlc
VLC ff_h263_mv_vlc
Definition: ituh263dec.c:101
ff_h263_decode_init
int ff_h263_decode_init(AVCodecContext *avctx)
Definition: h263dec.c:73
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:271
code
and forward the test the status of outputs and forward it to the corresponding return FFERROR_NOT_READY If the filters stores internally one or a few frame for some it can consider them to be part of the FIFO and delay acknowledging a status change accordingly Example code
Definition: filter_design.txt:178
ff_h263_decode_end
int ff_h263_decode_end(AVCodecContext *avctx)
Definition: h263dec.c:158
ff_h263_cbpy_vlc
VLC ff_h263_cbpy_vlc
Definition: ituh263dec.c:100
ff_h263_decode_gob_header
int ff_h263_decode_gob_header(MpegEncContext *s)
ff_h263_aspect_to_info
av_const int ff_h263_aspect_to_info(AVRational aspect)
Return the 4 bit value that specifies the given aspect ratio.
Definition: ituh263enc.c:90
pred
static const float pred[4]
Definition: siprdata.h:259
FF_MPV_FLAG_CBP_RD
#define FF_MPV_FLAG_CBP_RD
Definition: mpegvideo.h:585
ff_h263_decode_picture_header
int ff_h263_decode_picture_header(MpegEncContext *s)
Definition: ituh263dec.c:998
ff_mvtab
const uint8_t ff_mvtab[33][2]
Definition: h263data.c:88
AVCodecContext
main external API structure.
Definition: avcodec.h:383
VLC
Definition: vlc.h:26
ff_h263_pred_motion
int16_t * ff_h263_pred_motion(MpegEncContext *s, int block, int dir, int *px, int *py)
Definition: h263.c:318
ff_h263_pred_acdc
void ff_h263_pred_acdc(MpegEncContext *s, int16_t *block, int n)
Definition: h263.c:231
INT_BIT
#define INT_BIT
Definition: h263.h:31
ff_h263_encode_motion_vector
static void ff_h263_encode_motion_vector(MpegEncContext *s, int x, int y, int f_code)
Definition: h263.h:119
ff_h263_decode_frame
int ff_h263_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: h263dec.c:426
AVPacket
This structure stores compressed data.
Definition: packet.h:350
rl.h
block
The exact code depends on how similar the blocks are and how related they are to the block
Definition: filter_design.txt:207
ff_h263_decode_mb
int ff_h263_decode_mb(MpegEncContext *s, int16_t block[6][64])
Definition: ituh263dec.c:696
MpegEncContext
MpegEncContext.
Definition: mpegvideo.h:71
ff_h263_encode_mb
void ff_h263_encode_mb(MpegEncContext *s, int16_t block[6][64], int motion_x, int motion_y)
Definition: ituh263enc.c:448
ff_h263_encode_motion
void ff_h263_encode_motion(PutBitContext *pb, int val, int f_code)
Definition: ituh263enc.c:647
ff_h263_inter_MCBPC_vlc
VLC ff_h263_inter_MCBPC_vlc
Definition: ituh263dec.c:99