FFmpeg  4.0
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 char * s
Definition: avisynth_c.h:768
static const char * format[]
Definition: af_aiir.c:311
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:207
#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
AVCodec.
Definition: avcodec.h:3408
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:1640
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:3415
static const AVClass flv_class
Definition: flvenc.c:94
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:266
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:62
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:60
AVCodec ff_flv_encoder
Definition: flvenc.c:101
Predicted.
Definition: avutil.h:275