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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 #if !FF_API_ASPECT_EXTENDED
31 #define FF_ASPECT_EXTENDED 15
32 #endif
33 #define INT_BIT (CHAR_BIT * sizeof(int))
34 
35 // The defines below define the number of bits that are read at once for
36 // reading vlc values. Changing these may improve speed and data cache needs
37 // be aware though that decreasing them may need the number of stages that is
38 // passed to get_vlc* to be increased.
39 #define INTRA_MCBPC_VLC_BITS 6
40 #define INTER_MCBPC_VLC_BITS 7
41 #define CBPY_VLC_BITS 6
42 #define TEX_VLC_BITS 9
43 
44 #define H263_GOB_HEIGHT(h) ((h) <= 400 ? 1 : (h) <= 800 ? 2 : 4)
45 
48 extern VLC ff_h263_cbpy_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);
76 int ff_h263_pred_dc(MpegEncContext * s, int n, int16_t **dc_val_ptr);
77 void ff_h263_pred_acdc(MpegEncContext * s, int16_t *block, int n);
78 
79 
80 /**
81  * Print picture info if FF_DEBUG_PICT_INFO is set.
82  */
84 
87  int16_t block[6][64]);
88 
89 /**
90  * Return the value of the 3-bit "source format" syntax element.
91  * This represents some standard picture dimensions or indicates that
92  * width&height are explicitly stored later.
93  */
95 
98 void ff_h263_encode_motion(PutBitContext *pb, int val, int f_code);
99 
100 
101 static inline int h263_get_motion_length(int val, int f_code){
102  int l, bit_size, code;
103 
104  if (val == 0) {
105  return ff_mvtab[0][1];
106  } else {
107  bit_size = f_code - 1;
108  /* modulo encoding */
109  l= INT_BIT - 6 - bit_size;
110  val = (val<<l)>>l;
111  val--;
112  code = (val >> bit_size) + 1;
113 
114  return ff_mvtab[code][1] + 1 + bit_size;
115  }
116 }
117 
118 static inline void ff_h263_encode_motion_vector(MpegEncContext * s, int x, int y, int f_code){
120  skip_put_bits(&s->pb,
121  h263_get_motion_length(x, f_code)
122  +h263_get_motion_length(y, f_code));
123  }else{
124  ff_h263_encode_motion(&s->pb, x, f_code);
125  ff_h263_encode_motion(&s->pb, y, f_code);
126  }
127 }
128 
129 static inline int get_p_cbp(MpegEncContext * s,
130  int16_t block[6][64],
131  int motion_x, int motion_y){
132  int cbp, i;
133 
134  if (s->mpv_flags & FF_MPV_FLAG_CBP_RD) {
135  int best_cbpy_score= INT_MAX;
136  int best_cbpc_score= INT_MAX;
137  int cbpc = (-1), cbpy= (-1);
138  const int offset= (s->mv_type==MV_TYPE_16X16 ? 0 : 16) + (s->dquant ? 8 : 0);
139  const int lambda= s->lambda2 >> (FF_LAMBDA_SHIFT - 6);
140 
141  for(i=0; i<4; i++){
142  int score= ff_h263_inter_MCBPC_bits[i + offset] * lambda;
143  if(i&1) score += s->coded_score[5];
144  if(i&2) score += s->coded_score[4];
145 
146  if(score < best_cbpc_score){
147  best_cbpc_score= score;
148  cbpc= i;
149  }
150  }
151 
152  for(i=0; i<16; i++){
153  int score= ff_h263_cbpy_tab[i ^ 0xF][1] * lambda;
154  if(i&1) score += s->coded_score[3];
155  if(i&2) score += s->coded_score[2];
156  if(i&4) score += s->coded_score[1];
157  if(i&8) score += s->coded_score[0];
158 
159  if(score < best_cbpy_score){
160  best_cbpy_score= score;
161  cbpy= i;
162  }
163  }
164  cbp= cbpc + 4*cbpy;
165  if ((motion_x | motion_y | s->dquant) == 0 && s->mv_type==MV_TYPE_16X16){
166  if(best_cbpy_score + best_cbpc_score + 2*lambda >= 0)
167  cbp= 0;
168  }
169 
170  for (i = 0; i < 6; i++) {
171  if (s->block_last_index[i] >= 0 && ((cbp >> (5 - i))&1)==0 ){
172  s->block_last_index[i]= -1;
173  s->bdsp.clear_block(s->block[i]);
174  }
175  }
176  }else{
177  cbp= 0;
178  for (i = 0; i < 6; i++) {
179  if (s->block_last_index[i] >= 0)
180  cbp |= 1 << (5 - i);
181  }
182  }
183  return cbp;
184 }
185 
186 #endif /* AVCODEC_H263_H */
#define av_const
Definition: attributes.h:76
const char const char void * val
Definition: avisynth_c.h:634
const char * s
Definition: avisynth_c.h:631
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:35
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:249
int coded_score[12]
Definition: mpegvideo.h:320
mpegvideo header.
int mpv_flags
flags set by private options
Definition: mpegvideo.h:525
#define FF_LAMBDA_SHIFT
Definition: avutil.h:217
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:610
#define FF_MPV_FLAG_CBP_RD
Definition: mpegvideo.h:573
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
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
#define width
enum AVPixelFormat ff_h263_hwaccel_pixfmt_list_420[]
Definition: h263dec.c:721
int block_last_index[12]
last non zero coefficient in block
Definition: mpegvideo.h:83
int n
Definition: avisynth_c.h:547
void ff_h263_pred_acdc(MpegEncContext *s, int16_t *block, int n)
Definition: h263.c:222
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:266
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:1657
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 numerator/denominator
Definition: rational.h:43
static void ff_h263_encode_motion_vector(MpegEncContext *s, int x, int y, int f_code)
Definition: h263.h:118
int ff_h263_decode_picture_header(MpegEncContext *s)
Definition: ituh263dec.c:876
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:212
int16_t * ff_h263_pred_motion(MpegEncContext *s, int block, int dir, int *px, int *py)
Definition: h263.c:309
MpegEncContext.
Definition: mpegvideo.h:78
struct AVCodecContext * avctx
Definition: mpegvideo.h:95
PutBitContext pb
bit output
Definition: mpegvideo.h:148
rational numbers
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:497
static int get_p_cbp(MpegEncContext *s, int16_t block[6][64], int motion_x, int motion_y)
Definition: h263.h:129
int flags2
AV_CODEC_FLAG2_*.
Definition: avcodec.h:1759
int ff_h263_decode_gob_header(MpegEncContext *s)
static int h263_get_motion_length(int val, int f_code)
Definition: h263.h:101
int ff_h263_decode_motion(MpegEncContext *s, int pred, int f_code)
Definition: ituh263dec.c:254
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:1565
const uint8_t ff_mvtab[33][2]
Definition: h263data.c:90
#define INT_BIT
Definition: h263.h:33
static int16_t block[64]
Definition: dct-test.c:112