FFmpeg: libavcodec/vp9_superframe_split_bsf.c Source File

FFmpeg
vp9_superframe_split_bsf.c
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1 /*
2  * This file is part of FFmpeg.
3  *
4  * FFmpeg is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
7  * version 2.1 of the License, or (at your option) any later version.
8  *
9  * FFmpeg is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * Lesser General Public License for more details.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with FFmpeg; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17  */
18 
19 /**
20  * @file
21  * This bitstream filter splits VP9 superframes into packets containing
22  * just one frame.
23  */
24 
25 #include <stddef.h>
26 
27 #include "avcodec.h"
28 #include "bsf.h"
29 #include "bytestream.h"
30 #include "get_bits.h"
31 
32  typedef struct VP9SFSplitContext {
33   AVPacket buffer_pkt;
34 
35   int nb_frames;
36   int next_frame;
37   size_t next_frame_offset;
38   int sizes[8];
39 } VP9SFSplitContext;
40 
41  static int vp9_superframe_split_filter(AVBSFContext *ctx, AVPacket *out)
42 {
43  VP9SFSplitContext *s = ctx->priv_data;
44  AVPacket *in;
45  int i, j, ret, marker;
46  int is_superframe = !!s->buffer_pkt.data;
47 
48  if (!s->buffer_pkt.data) {
49  ret = ff_bsf_get_packet_ref(ctx, &s->buffer_pkt);
50  if (ret < 0)
51  return ret;
52  in = &s->buffer_pkt;
53 
54  marker = in->data[in->size - 1];
55  if ((marker & 0xe0) == 0xc0) {
56  int length_size = 1 + ((marker >> 3) & 0x3);
57  int nb_frames = 1 + (marker & 0x7);
58  int idx_size = 2 + nb_frames * length_size;
59 
60  if (in->size >= idx_size && in->data[in->size - idx_size] == marker) {
61  GetByteContext bc;
62  int64_t total_size = 0;
63 
64  bytestream2_init(&bc, in->data + in->size + 1 - idx_size,
65  nb_frames * length_size);
66 
67  for (i = 0; i < nb_frames; i++) {
68  int frame_size = 0;
69  for (j = 0; j < length_size; j++)
70  frame_size |= bytestream2_get_byte(&bc) << (j * 8);
71 
72  total_size += frame_size;
73  if (frame_size < 0 || total_size > in->size - idx_size) {
74  av_log(ctx, AV_LOG_ERROR,
75  "Invalid frame size in a superframe: %d\n", frame_size);
76  ret = AVERROR(EINVAL);
77  goto fail;
78  }
79  s->sizes[i] = frame_size;
80  }
81  s->nb_frames = nb_frames;
82  s->next_frame = 0;
83  s->next_frame_offset = 0;
84  is_superframe = 1;
85  }
86  }
87  }
88 
89  if (is_superframe) {
90  GetBitContext gb;
91  int profile, invisible = 0;
92 
93  ret = av_packet_ref(out, &s->buffer_pkt);
94  if (ret < 0)
95  goto fail;
96 
97  out->data += s->next_frame_offset;
98  out->size = s->sizes[s->next_frame];
99 
100  s->next_frame_offset += out->size;
101  s->next_frame++;
102 
103  if (s->next_frame >= s->nb_frames)
104  av_packet_unref(&s->buffer_pkt);
105 
106  ret = init_get_bits8(&gb, out->data, out->size);
107  if (ret < 0)
108  goto fail;
109 
110  get_bits(&gb, 2); // frame_marker
111  profile = get_bits1(&gb);
112  profile |= get_bits1(&gb) << 1;
113  if (profile == 3)
114  get_bits1(&gb);
115  if (!get_bits1(&gb)) {
116  get_bits1(&gb);
117  invisible = !get_bits1(&gb);
118  }
119 
120  if (invisible)
121  out->pts = AV_NOPTS_VALUE;
122 
123  } else {
124  av_packet_move_ref(out, &s->buffer_pkt);
125  }
126 
127  return 0;
128 fail:
129  if (ret < 0)
130  av_packet_unref(out);
131  av_packet_unref(&s->buffer_pkt);
132  return ret;
133 }
134 
135  static void vp9_superframe_split_uninit(AVBSFContext *ctx)
136 {
137  VP9SFSplitContext *s = ctx->priv_data;
138  av_packet_unref(&s->buffer_pkt);
139 }
140 
141  const AVBitStreamFilter ff_vp9_superframe_split_bsf = {
142  .name = "vp9_superframe_split",
143  .priv_data_size = sizeof(VP9SFSplitContext),
144  .close = vp9_superframe_split_uninit,
145  .filter = vp9_superframe_split_filter,
146  .codec_ids = (const enum AVCodecID []){ AV_CODEC_ID_VP9, AV_CODEC_ID_NONE },
147 };
AV_CODEC_ID_VP9
Definition: avcodec.h:386
s
const char * s
Definition: avisynth_c.h:768
AV_CODEC_ID_NONE
Definition: avcodec.h:216
ff_vp9_superframe_split_bsf
const AVBitStreamFilter ff_vp9_superframe_split_bsf
Definition: vp9_superframe_split_bsf.c:141
get_bits
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:269
AVBSFContext
The bitstream filter state.
Definition: avcodec.h:5687
AVPacket::size
int size
Definition: avcodec.h:1431
bytestream2_init
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:133
AVBSFContext::priv_data
void * priv_data
Opaque filter-specific private data.
Definition: avcodec.h:5708
filter
static void filter(int16_t *output, ptrdiff_t out_stride, int16_t *low, ptrdiff_t low_stride, int16_t *high, ptrdiff_t high_stride, int len, int clip)
Definition: cfhd.c:114
AVBitStreamFilter::name
const char * name
Definition: avcodec.h:5737
AVPacket::data
uint8_t * data
Definition: avcodec.h:1430
av_packet_move_ref
void av_packet_move_ref(AVPacket *dst, AVPacket *src)
Move every field in src to dst and reset src.
Definition: avpacket.c:647
get_bits.h
bitstream reader API header.
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
av_packet_ref
int av_packet_ref(AVPacket *dst, const AVPacket *src)
Setup a new reference to the data described by a given packet.
Definition: avpacket.c:601
AVCodecID
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: avcodec.h:215
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
AVERROR
#define AVERROR(e)
Definition: error.h:43
vp9_superframe_split_uninit
static void vp9_superframe_split_uninit(AVBSFContext *ctx)
Definition: vp9_superframe_split_bsf.c:135
fail
#define fail()
Definition: checkasm.h:116
ctx
AVFormatContext * ctx
Definition: movenc.c:48
frame_size
int frame_size
Definition: mxfenc.c:1947
avcodec.h
Libavcodec external API header.
init_get_bits8
static int init_get_bits8(GetBitContext *s, const uint8_t *buffer, int byte_size)
Initialize GetBitContext.
Definition: get_bits.h:464
av_packet_unref
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:592
in
uint8_t pi<< 24) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0f/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S16, int16_t,(*(constint16_t *) pi >>8)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0f/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S32, int32_t,(*(constint32_t *) pi >>24)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0f/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_FLT, float, av_clip_uint8(lrintf(*(constfloat *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_FLT, float, av_clip_int16(lrintf(*(constfloat *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_FLT, float, av_clipl_int32(llrintf(*(constfloat *) pi *(1U<< 31)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_DBL, double, av_clip_uint8(lrint(*(constdouble *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_DBL, double, av_clip_int16(lrint(*(constdouble *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_DBL, double, av_clipl_int32(llrint(*(constdouble *) pi *(1U<< 31))))#defineSET_CONV_FUNC_GROUP(ofmt, ifmt) staticvoidset_generic_function(AudioConvert *ac){}voidff_audio_convert_free(AudioConvert **ac){if(!*ac) return;ff_dither_free(&(*ac) ->dc);av_freep(ac);}AudioConvert *ff_audio_convert_alloc(AVAudioResampleContext *avr, enumAVSampleFormatout_fmt, enumAVSampleFormatin_fmt, intchannels, intsample_rate, intapply_map){AudioConvert *ac;intin_planar, out_planar;ac=av_mallocz(sizeof(*ac));if(!ac) returnNULL;ac->avr=avr;ac->out_fmt=out_fmt;ac->in_fmt=in_fmt;ac->channels=channels;ac->apply_map=apply_map;if(avr->dither_method!=AV_RESAMPLE_DITHER_NONE &&av_get_packed_sample_fmt(out_fmt)==AV_SAMPLE_FMT_S16 &&av_get_bytes_per_sample(in_fmt)>2){ac->dc=ff_dither_alloc(avr, out_fmt, in_fmt, channels, sample_rate, apply_map);if(!ac->dc){av_free(ac);returnNULL;}returnac;}in_planar=ff_sample_fmt_is_planar(in_fmt, channels);out_planar=ff_sample_fmt_is_planar(out_fmt, channels);if(in_planar==out_planar){ac->func_type=CONV_FUNC_TYPE_FLAT;ac->planes=in_planar?ac->channels:1;}elseif(in_planar) ac->func_type=CONV_FUNC_TYPE_INTERLEAVE;elseac->func_type=CONV_FUNC_TYPE_DEINTERLEAVE;set_generic_function(ac);if(ARCH_AARCH64) ff_audio_convert_init_aarch64(ac);if(ARCH_ARM) ff_audio_convert_init_arm(ac);if(ARCH_X86) ff_audio_convert_init_x86(ac);returnac;}intff_audio_convert(AudioConvert *ac, AudioData *out, AudioData *in){intuse_generic=1;intlen=in->nb_samples;intp;if(ac->dc){av_log(ac->avr, AV_LOG_TRACE,"%dsamples-audio_convert:%sto%s(dithered)\n", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt));returnff_convert_dither(ac-> in
Definition: audio_convert.c:194
get_bits1
static unsigned int get_bits1(GetBitContext *s)
Definition: get_bits.h:321
vp9_superframe_split_filter
static int vp9_superframe_split_filter(AVBSFContext *ctx, AVPacket *out)
Definition: vp9_superframe_split_bsf.c:41
profile
mfxU16 profile
Definition: qsvenc.c:44
codec_ids
static enum AVCodecID codec_ids[]
Definition: aac_adtstoasc_bsf.c:148
out
FILE * out
Definition: movenc.c:54
AVPacket
This structure stores compressed data.
Definition: avcodec.h:1407
ff_bsf_get_packet_ref
int ff_bsf_get_packet_ref(AVBSFContext *ctx, AVPacket *pkt)
Called by bitstream filters to get packet for filtering.
Definition: bsf.c:228
AVPacket::pts
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1423
AV_NOPTS_VALUE
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
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