FFmpeg
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
flvenc.c
Go to the documentation of this file.
1 /*
2  * FLV Encoding specific code.
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 
21 #include "flv.h"
22 #include "h263.h"
23 #include "mpegvideo.h"
24 
25 void ff_flv_encode_picture_header(MpegEncContext *s, int picture_number)
26 {
27  int format;
28 
30 
31  put_bits(&s->pb, 17, 1);
32  /* 0: h263 escape codes 1: 11-bit escape codes */
33  put_bits(&s->pb, 5, (s->h263_flv - 1));
34  put_bits(&s->pb, 8,
35  (((int64_t) s->picture_number * 30 * s->avctx->time_base.num) / // FIXME use timestamp
36  s->avctx->time_base.den) & 0xff); /* TemporalReference */
37  if (s->width == 352 && s->height == 288)
38  format = 2;
39  else if (s->width == 176 && s->height == 144)
40  format = 3;
41  else if (s->width == 128 && s->height == 96)
42  format = 4;
43  else if (s->width == 320 && s->height == 240)
44  format = 5;
45  else if (s->width == 160 && s->height == 120)
46  format = 6;
47  else if (s->width <= 255 && s->height <= 255)
48  format = 0; /* use 1 byte width & height */
49  else
50  format = 1; /* use 2 bytes width & height */
51  put_bits(&s->pb, 3, format); /* PictureSize */
52  if (format == 0) {
53  put_bits(&s->pb, 8, s->width);
54  put_bits(&s->pb, 8, s->height);
55  } else if (format == 1) {
56  put_bits(&s->pb, 16, s->width);
57  put_bits(&s->pb, 16, s->height);
58  }
59  put_bits(&s->pb, 2, s->pict_type == AV_PICTURE_TYPE_P); /* PictureType */
60  put_bits(&s->pb, 1, 1); /* DeblockingFlag: on */
61  put_bits(&s->pb, 5, s->qscale); /* Quantizer */
62  put_bits(&s->pb, 1, 0); /* ExtraInformation */
63 
64  if (s->h263_aic) {
65  s->y_dc_scale_table =
67  } else {
68  s->y_dc_scale_table =
70  }
71 }
72 
73 void ff_flv2_encode_ac_esc(PutBitContext *pb, int slevel, int level,
74  int run, int last)
75 {
76  if (level < 64) { // 7-bit level
77  put_bits(pb, 1, 0);
78  put_bits(pb, 1, last);
79  put_bits(pb, 6, run);
80 
81  put_sbits(pb, 7, slevel);
82  } else {
83  /* 11-bit level */
84  put_bits(pb, 1, 1);
85  put_bits(pb, 1, last);
86  put_bits(pb, 6, run);
87 
88  put_sbits(pb, 11, slevel);
89  }
90 }
91 
93 
95  .name = "flv",
96  .long_name = NULL_IF_CONFIG_SMALL("FLV / Sorenson Spark / Sorenson H.263 (Flash Video)"),
97  .type = AVMEDIA_TYPE_VIDEO,
98  .id = AV_CODEC_ID_FLV1,
99  .priv_data_size = sizeof(MpegEncContext),
101  .encode2 = ff_mpv_encode_picture,
102  .close = ff_mpv_encode_end,
103  .pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_YUV420P,
105  .priv_class = &flv_class,
106 };