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h263.h
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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 INTRA_MCBPC_VLC_BITS 6
38 #define INTER_MCBPC_VLC_BITS 7
39 #define CBPY_VLC_BITS 6
40 #define TEX_VLC_BITS 9
41 
42 #define H263_GOB_HEIGHT(h) ((h) <= 400 ? 1 : (h) <= 800 ? 2 : 4)
43 
46 extern VLC ff_h263_cbpy_vlc;
47 
49 
50 
51 int ff_h263_decode_motion(MpegEncContext * s, int pred, int f_code);
55  void *data, int *got_frame,
56  AVPacket *avpkt);
59  int16_t block[6][64],
60  int motion_x, int motion_y);
61 void ff_h263_encode_picture_header(MpegEncContext *s, int picture_number);
62 void ff_h263_encode_gob_header(MpegEncContext * s, int mb_line);
63 int16_t *ff_h263_pred_motion(MpegEncContext * s, int block, int dir,
64  int *px, int *py);
66 void ff_h263_decode_init_vlc(void);
74 int ff_h263_pred_dc(MpegEncContext * s, int n, int16_t **dc_val_ptr);
75 void ff_h263_pred_acdc(MpegEncContext * s, int16_t *block, int n);
76 
77 
78 /**
79  * Print picture info if FF_DEBUG_PICT_INFO is set.
80  */
82 
85  int16_t block[6][64]);
86 
87 /**
88  * Return the value of the 3-bit "source format" syntax element.
89  * This represents some standard picture dimensions or indicates that
90  * width&height are explicitly stored later.
91  */
93 
96 void ff_h263_encode_motion(PutBitContext *pb, int val, int f_code);
97 
98 
99 static inline int h263_get_motion_length(int val, int f_code){
100  int l, bit_size, code;
101 
102  if (val == 0) {
103  return ff_mvtab[0][1];
104  } else {
105  bit_size = f_code - 1;
106  /* modulo encoding */
107  l= INT_BIT - 6 - bit_size;
108  val = (val<<l)>>l;
109  val--;
110  code = (val >> bit_size) + 1;
111 
112  return ff_mvtab[code][1] + 1 + bit_size;
113  }
114 }
115 
116 static inline void ff_h263_encode_motion_vector(MpegEncContext * s, int x, int y, int f_code){
118  skip_put_bits(&s->pb,
119  h263_get_motion_length(x, f_code)
120  +h263_get_motion_length(y, f_code));
121  }else{
122  ff_h263_encode_motion(&s->pb, x, f_code);
123  ff_h263_encode_motion(&s->pb, y, f_code);
124  }
125 }
126 
127 static inline int get_p_cbp(MpegEncContext * s,
128  int16_t block[6][64],
129  int motion_x, int motion_y){
130  int cbp, i;
131 
132  if (s->mpv_flags & FF_MPV_FLAG_CBP_RD) {
133  int best_cbpy_score= INT_MAX;
134  int best_cbpc_score= INT_MAX;
135  int cbpc = (-1), cbpy= (-1);
136  const int offset= (s->mv_type==MV_TYPE_16X16 ? 0 : 16) + (s->dquant ? 8 : 0);
137  const int lambda= s->lambda2 >> (FF_LAMBDA_SHIFT - 6);
138 
139  for(i=0; i<4; i++){
140  int score= ff_h263_inter_MCBPC_bits[i + offset] * lambda;
141  if(i&1) score += s->coded_score[5];
142  if(i&2) score += s->coded_score[4];
143 
144  if(score < best_cbpc_score){
145  best_cbpc_score= score;
146  cbpc= i;
147  }
148  }
149 
150  for(i=0; i<16; i++){
151  int score= ff_h263_cbpy_tab[i ^ 0xF][1] * lambda;
152  if(i&1) score += s->coded_score[3];
153  if(i&2) score += s->coded_score[2];
154  if(i&4) score += s->coded_score[1];
155  if(i&8) score += s->coded_score[0];
156 
157  if(score < best_cbpy_score){
158  best_cbpy_score= score;
159  cbpy= i;
160  }
161  }
162  cbp= cbpc + 4*cbpy;
163  if ((motion_x | motion_y | s->dquant) == 0 && s->mv_type==MV_TYPE_16X16){
164  if(best_cbpy_score + best_cbpc_score + 2*lambda >= 0)
165  cbp= 0;
166  }
167 
168  for (i = 0; i < 6; i++) {
169  if (s->block_last_index[i] >= 0 && ((cbp >> (5 - i))&1)==0 ){
170  s->block_last_index[i]= -1;
171  s->bdsp.clear_block(s->block[i]);
172  }
173  }
174  }else{
175  cbp= 0;
176  for (i = 0; i < 6; i++) {
177  if (s->block_last_index[i] >= 0)
178  cbp |= 1 << (5 - i);
179  }
180  }
181  return cbp;
182 }
183 
184 #endif /* AVCODEC_H263_H */
#define av_const
Definition: attributes.h:76
const char const char void * val
Definition: avisynth_c.h:771
const char * s
Definition: avisynth_c.h:768
void ff_h263_encode_picture_header(MpegEncContext *s, int picture_number)
Definition: ituh263enc.c:103
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
void(* clear_block)(int16_t *block)
Definition: blockdsp.h:36
void ff_h263_encode_init(MpegEncContext *s)
Definition: ituh263enc.c:761
int ff_h263_pred_dc(MpegEncContext *s, int n, int16_t **dc_val_ptr)
Definition: h263.c:94
VLC ff_h263_intra_MCBPC_vlc
Definition: ituh263dec.c:98
VLC ff_h263_cbpy_vlc
Definition: ituh263dec.c:100
static void skip_put_bits(PutBitContext *s, int n)
Skip the given number of bits.
Definition: put_bits.h:346
int coded_score[12]
Definition: mpegvideo.h:317
mpegvideo header.
int mpv_flags
flags set by private options
Definition: mpegvideo.h:523
#define FF_LAMBDA_SHIFT
Definition: avutil.h:225
void ff_h263_encode_motion(PutBitContext *pb, int val, int f_code)
Definition: ituh263enc.c:646
int ff_h263_decode_mb(MpegEncContext *s, int16_t block[6][64])
Definition: ituh263dec.c:682
#define FF_MPV_FLAG_CBP_RD
Definition: mpegvideo.h:571
static int16_t block[64]
Definition: dct.c:115
void ff_h263_decode_init_vlc(void)
Definition: ituh263dec.c:108
void ff_h263_loop_filter(MpegEncContext *s)
Definition: h263.c:135
H.263 tables.
int ff_intel_h263_decode_picture_header(MpegEncContext *s)
Definition: intelh263dec.c:27
#define height
int ff_h263_decode_mba(MpegEncContext *s)
Definition: ituh263dec.c:139
void ff_init_qscale_tab(MpegEncContext *s)
init s->current_picture.qscale_table from s->lambda_table
bitstream reader API header.
int dquant
qscale difference to prev qscale
Definition: mpegvideo.h:207
uint16_t width
Definition: gdv.c:47
av_const int ff_h263_aspect_to_info(AVRational aspect)
Return the 4 bit value that specifies the given aspect ratio.
Definition: ituh263enc.c:89
rl header.
static const uint8_t offset[127][2]
Definition: vf_spp.c:92
Definition: vlc.h:26
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:266
int ff_h263_decode_init(AVCodecContext *avctx)
Definition: h263dec.c:62
VLC ff_h263_inter_MCBPC_vlc
Definition: ituh263dec.c:99
const uint8_t ff_h263_inter_MCBPC_bits[28]
Definition: h263data.c:49
int ff_h263_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: h263dec.c:409
enum AVPixelFormat ff_h263_hwaccel_pixfmt_list_420[]
Definition: h263dec.c:714
int block_last_index[12]
last non zero coefficient in block
Definition: mpegvideo.h:83
int n
Definition: avisynth_c.h:684
void ff_h263_pred_acdc(MpegEncContext *s, int16_t *block, int n)
Definition: h263.c:220
int av_const h263_get_picture_format(int width, int height)
Return the value of the 3-bit "source format" syntax element.
static const float pred[4]
Definition: siprdata.h:259
#define MV_TYPE_16X16
1 vector for the whole mb
Definition: mpegvideo.h:263
unsigned int lambda2
(lambda*lambda) >> FF_LAMBDA_SHIFT
Definition: mpegvideo.h:204
BlockDSPContext bdsp
Definition: mpegvideo.h:223
main external API structure.
Definition: avcodec.h:1488
void ff_h263_encode_mba(MpegEncContext *s)
Definition: ituh263enc.c:825
void ff_h263_encode_gob_header(MpegEncContext *s, int mb_line)
Encode a group of blocks header.
Definition: ituh263enc.c:240
Rational number (pair of numerator and denominator).
Definition: rational.h:58
static void ff_h263_encode_motion_vector(MpegEncContext *s, int x, int y, int f_code)
Definition: h263.h:116
int ff_h263_decode_picture_header(MpegEncContext *s)
Definition: ituh263dec.c:984
const uint8_t ff_h263_cbpy_tab[16][2]
Definition: h263data.c:84
int ff_h263_resync(MpegEncContext *s)
Decode the group of blocks / video packet header.
Definition: ituh263dec.c:213
int16_t * ff_h263_pred_motion(MpegEncContext *s, int block, int dir, int *px, int *py)
Definition: h263.c:307
MpegEncContext.
Definition: mpegvideo.h:78
struct AVCodecContext * avctx
Definition: mpegvideo.h:95
PutBitContext pb
bit output
Definition: mpegvideo.h:148
Utilties for rational number calculation.
void ff_h263_encode_mb(MpegEncContext *s, int16_t block[6][64], int motion_x, int motion_y)
Definition: ituh263enc.c:447
#define AV_CODEC_FLAG2_NO_OUTPUT
Skip bitstream encoding.
Definition: avcodec.h:902
int ff_h263_decode_end(AVCodecContext *avctx)
Definition: h263dec.c:149
void ff_h263_update_motion_val(MpegEncContext *s)
Definition: h263.c:42
int16_t(* block)[64]
points to one of the following blocks
Definition: mpegvideo.h:495
static int get_p_cbp(MpegEncContext *s, int16_t block[6][64], int motion_x, int motion_y)
Definition: h263.h:127
int flags2
AV_CODEC_FLAG2_*.
Definition: avcodec.h:1575
int ff_h263_decode_gob_header(MpegEncContext *s)
static int h263_get_motion_length(int val, int f_code)
Definition: h263.h:99
int ff_h263_decode_motion(MpegEncContext *s, int pred, int f_code)
Definition: ituh263dec.c:255
void ff_h263_show_pict_info(MpegEncContext *s)
Print picture info if FF_DEBUG_PICT_INFO is set.
Definition: ituh263dec.c:76
AVPixelFormat
Pixel format.
Definition: pixfmt.h:60
This structure stores compressed data.
Definition: avcodec.h:1377
const uint8_t ff_mvtab[33][2]
Definition: h263data.c:90
#define INT_BIT
Definition: h263.h:31