FFmpeg
flvenc.c
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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 "h263data.h"
24 #include "mpegvideo.h"
25 #include "mpegvideodata.h"
26 
27 void ff_flv_encode_picture_header(MpegEncContext *s, int picture_number)
28 {
29  int format;
30 
32 
33  put_bits(&s->pb, 17, 1);
34  /* 0: H.263 escape codes 1: 11-bit escape codes */
35  put_bits(&s->pb, 5, (s->h263_flv - 1));
36  put_bits(&s->pb, 8,
37  (((int64_t) s->picture_number * 30 * s->avctx->time_base.num) / // FIXME use timestamp
38  s->avctx->time_base.den) & 0xff); /* TemporalReference */
39  if (s->width == 352 && s->height == 288)
40  format = 2;
41  else if (s->width == 176 && s->height == 144)
42  format = 3;
43  else if (s->width == 128 && s->height == 96)
44  format = 4;
45  else if (s->width == 320 && s->height == 240)
46  format = 5;
47  else if (s->width == 160 && s->height == 120)
48  format = 6;
49  else if (s->width <= 255 && s->height <= 255)
50  format = 0; /* use 1 byte width & height */
51  else
52  format = 1; /* use 2 bytes width & height */
53  put_bits(&s->pb, 3, format); /* PictureSize */
54  if (format == 0) {
55  put_bits(&s->pb, 8, s->width);
56  put_bits(&s->pb, 8, s->height);
57  } else if (format == 1) {
58  put_bits(&s->pb, 16, s->width);
59  put_bits(&s->pb, 16, s->height);
60  }
61  put_bits(&s->pb, 2, s->pict_type == AV_PICTURE_TYPE_P); /* PictureType */
62  put_bits(&s->pb, 1, 1); /* DeblockingFlag: on */
63  put_bits(&s->pb, 5, s->qscale); /* Quantizer */
64  put_bits(&s->pb, 1, 0); /* ExtraInformation */
65 
66  if (s->h263_aic) {
67  s->y_dc_scale_table =
68  s->c_dc_scale_table = ff_aic_dc_scale_table;
69  } else {
70  s->y_dc_scale_table =
71  s->c_dc_scale_table = ff_mpeg1_dc_scale_table;
72  }
73 }
74 
75 void ff_flv2_encode_ac_esc(PutBitContext *pb, int slevel, int level,
76  int run, int last)
77 {
78  if (level < 64) { // 7-bit level
79  put_bits(pb, 1, 0);
80  put_bits(pb, 1, last);
81  put_bits(pb, 6, run);
82 
83  put_sbits(pb, 7, slevel);
84  } else {
85  /* 11-bit level */
86  put_bits(pb, 1, 1);
87  put_bits(pb, 1, last);
88  put_bits(pb, 6, run);
89 
90  put_sbits(pb, 11, slevel);
91  }
92 }
93 
94 static const AVClass flv_class = {
95  .class_name = "flv encoder",
96  .item_name = av_default_item_name,
97  .option = ff_mpv_generic_options,
98  .version = LIBAVUTIL_VERSION_INT,
99 };
100 
102  .name = "flv",
103  .long_name = NULL_IF_CONFIG_SMALL("FLV / Sorenson Spark / Sorenson H.263 (Flash Video)"),
104  .type = AVMEDIA_TYPE_VIDEO,
105  .id = AV_CODEC_ID_FLV1,
106  .priv_data_size = sizeof(MpegEncContext),
108  .encode2 = ff_mpv_encode_picture,
109  .close = ff_mpv_encode_end,
110  .pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_YUV420P,
112  .priv_class = &flv_class,
113 };
AVCodec
AVCodec.
Definition: codec.h:190
h263data.h
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
level
uint8_t level
Definition: svq3.c:210
init
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
ff_mpeg1_dc_scale_table
const uint8_t ff_mpeg1_dc_scale_table[128]
Definition: mpegvideodata.c:33
put_sbits
static void put_sbits(PutBitContext *pb, int n, int32_t value)
Definition: put_bits.h:240
ff_flv_encode_picture_header
void ff_flv_encode_picture_header(MpegEncContext *s, int picture_number)
Definition: flvenc.c:27
put_bits
static void put_bits(Jpeg2000EncoderContext *s, int val, int n)
put n times val bit
Definition: j2kenc.c:208
mpegvideo.h
flv.h
s
#define s(width, name)
Definition: cbs_vp9.c:257
ff_mpv_encode_init
int ff_mpv_encode_init(AVCodecContext *avctx)
Definition: mpegvideo_enc.c:288
format
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample format(the sample packing is implied by the sample format) and sample rate. The lists are not just lists
ff_mpv_encode_picture
int ff_mpv_encode_picture(AVCodecContext *avctx, AVPacket *pkt, const AVFrame *frame, int *got_packet)
Definition: mpegvideo_enc.c:1824
pix_fmts
static enum AVPixelFormat pix_fmts[]
Definition: libkvazaar.c:275
AV_PIX_FMT_YUV420P
@ AV_PIX_FMT_YUV420P
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
Definition: pixfmt.h:66
PutBitContext
Definition: put_bits.h:35
ff_flv_encoder
AVCodec ff_flv_encoder
Definition: flvenc.c:101
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:67
run
uint8_t run
Definition: svq3.c:209
av_default_item_name
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:235
avpriv_align_put_bits
void avpriv_align_put_bits(PutBitContext *s)
Pad the bitstream with zeros up to the next byte boundary.
Definition: bitstream.c:48
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:188
mpegvideodata.h
ff_mpv_generic_options
const AVOption ff_mpv_generic_options[]
Definition: mpegvideo_enc.c:85
ff_mpv_encode_end
int ff_mpv_encode_end(AVCodecContext *avctx)
Definition: mpegvideo_enc.c:1072
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:197
ff_flv2_encode_ac_esc
void ff_flv2_encode_ac_esc(PutBitContext *pb, int slevel, int level, int run, int last)
Definition: flvenc.c:75
AVClass::class_name
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:72
ff_aic_dc_scale_table
const uint8_t ff_aic_dc_scale_table[32]
Definition: h263data.c:247
AV_PIX_FMT_NONE
@ AV_PIX_FMT_NONE
Definition: pixfmt.h:65
AV_PICTURE_TYPE_P
@ AV_PICTURE_TYPE_P
Predicted.
Definition: avutil.h:275
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
flv_class
static const AVClass flv_class
Definition: flvenc.c:94
AV_CODEC_ID_FLV1
@ AV_CODEC_ID_FLV1
Definition: codec_id.h:70
MpegEncContext
MpegEncContext.
Definition: mpegvideo.h:81
h263.h