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 =
69  } else {
70  s->y_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 };
int picture_number
Definition: mpegvideo.h:127
const uint8_t * y_dc_scale_table
qscale -> y_dc_scale table
Definition: mpegvideo.h:188
static void put_sbits(PutBitContext *pb, int n, int32_t value)
Definition: put_bits.h:240
static void put_bits(Jpeg2000EncoderContext *s, int val, int n)
put n times val bit
Definition: j2kenc.c:208
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
int num
Numerator.
Definition: rational.h:59
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:191
void avpriv_align_put_bits(PutBitContext *s)
Pad the bitstream with zeros up to the next byte boundary.
Definition: bitstream.c:48
mpegvideo header.
uint8_t run
Definition: svq3.c:206
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
AVCodec.
Definition: avcodec.h:3492
int qscale
QP.
Definition: mpegvideo.h:204
int h263_aic
Advanced INTRA Coding (AIC)
Definition: mpegvideo.h:87
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avcodec.h:1691
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
const AVOption ff_mpv_generic_options[]
Definition: mpegvideo_enc.c:85
const uint8_t ff_mpeg1_dc_scale_table[128]
Definition: mpegvideodata.c:34
H.263 tables.
void ff_flv2_encode_ac_esc(PutBitContext *pb, int slevel, int level, int run, int last)
Definition: flvenc.c:75
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
const char * name
Name of the codec implementation.
Definition: avcodec.h:3499
static const AVClass flv_class
Definition: flvenc.c:94
#define s(width, name)
Definition: cbs_vp9.c:257
const uint8_t ff_aic_dc_scale_table[32]
Definition: h263data.c:247
int h263_flv
use flv H.263 header
Definition: mpegvideo.h:110
void ff_flv_encode_picture_header(MpegEncContext *s, int picture_number)
Definition: flvenc.c:27
int height
picture size. must be a multiple of 16
Definition: mpegvideo.h:100
int ff_mpv_encode_init(AVCodecContext *avctx)
Describe the class of an AVClass context structure.
Definition: log.h:67
int pict_type
AV_PICTURE_TYPE_I, AV_PICTURE_TYPE_P, AV_PICTURE_TYPE_B, ...
Definition: mpegvideo.h:212
static enum AVPixelFormat pix_fmts[]
Definition: libkvazaar.c:275
const uint8_t * c_dc_scale_table
qscale -> c_dc_scale table
Definition: mpegvideo.h:189
uint8_t level
Definition: svq3.c:207
MpegEncContext.
Definition: mpegvideo.h:81
struct AVCodecContext * avctx
Definition: mpegvideo.h:98
PutBitContext pb
bit output
Definition: mpegvideo.h:151
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
Definition: pixfmt.h:66
int den
Denominator.
Definition: rational.h:60
int ff_mpv_encode_end(AVCodecContext *avctx)
int ff_mpv_encode_picture(AVCodecContext *avctx, AVPacket *pkt, const AVFrame *frame, int *got_packet)
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
AVCodec ff_flv_encoder
Definition: flvenc.c:101
Predicted.
Definition: avutil.h:275