FFmpeg
hevc_mp4toannexb_bsf.c
Go to the documentation of this file.
1 /*
2  * HEVC MP4 to Annex B byte stream format filter
3  * copyright (c) 2015 Anton Khirnov
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include <string.h>
23 
24 #include "libavutil/intreadwrite.h"
25 #include "libavutil/mem.h"
26 
27 #include "avcodec.h"
28 #include "bsf.h"
29 #include "bsf_internal.h"
30 #include "bytestream.h"
31 #include "hevc.h"
32 
33 #define MIN_HEVCC_LENGTH 23
34 
35 typedef struct HEVCBSFContext {
36  uint8_t length_size;
39 
41 {
42  GetByteContext gb;
43  int length_size, num_arrays, i, j;
44  int ret = 0;
45 
46  uint8_t *new_extradata = NULL;
47  size_t new_extradata_size = 0;
48 
49  bytestream2_init(&gb, ctx->par_in->extradata, ctx->par_in->extradata_size);
50 
51  bytestream2_skip(&gb, 21);
52  length_size = (bytestream2_get_byte(&gb) & 3) + 1;
53  num_arrays = bytestream2_get_byte(&gb);
54 
55  for (i = 0; i < num_arrays; i++) {
56  int type = bytestream2_get_byte(&gb) & 0x3f;
57  int cnt = bytestream2_get_be16(&gb);
58 
59  if (!(type == HEVC_NAL_VPS || type == HEVC_NAL_SPS || type == HEVC_NAL_PPS ||
61  av_log(ctx, AV_LOG_ERROR, "Invalid NAL unit type in extradata: %d\n",
62  type);
64  goto fail;
65  }
66 
67  for (j = 0; j < cnt; j++) {
68  int nalu_len = bytestream2_get_be16(&gb);
69 
70  if (4 + AV_INPUT_BUFFER_PADDING_SIZE + nalu_len > SIZE_MAX - new_extradata_size) {
72  goto fail;
73  }
74  ret = av_reallocp(&new_extradata, new_extradata_size + nalu_len + 4 + AV_INPUT_BUFFER_PADDING_SIZE);
75  if (ret < 0)
76  goto fail;
77 
78  AV_WB32(new_extradata + new_extradata_size, 1); // add the startcode
79  bytestream2_get_buffer(&gb, new_extradata + new_extradata_size + 4, nalu_len);
80  new_extradata_size += 4 + nalu_len;
81  memset(new_extradata + new_extradata_size, 0, AV_INPUT_BUFFER_PADDING_SIZE);
82  }
83  }
84 
85  av_freep(&ctx->par_out->extradata);
86  ctx->par_out->extradata = new_extradata;
87  ctx->par_out->extradata_size = new_extradata_size;
88 
89  if (!new_extradata_size)
90  av_log(ctx, AV_LOG_WARNING, "No parameter sets in the extradata\n");
91 
92  return length_size;
93 fail:
94  av_freep(&new_extradata);
95  return ret;
96 }
97 
99 {
101  int ret;
102 
103  if (ctx->par_in->extradata_size < MIN_HEVCC_LENGTH ||
104  AV_RB24(ctx->par_in->extradata) == 1 ||
105  AV_RB32(ctx->par_in->extradata) == 1) {
107  "The input looks like it is Annex B already\n");
108  } else {
110  if (ret < 0)
111  return ret;
112  s->length_size = ret;
113  s->extradata_parsed = 1;
114  }
115 
116  return 0;
117 }
118 
120 {
122  AVPacket *in;
123  GetByteContext gb;
124 
125  int got_irap = 0;
126  int i, ret = 0;
127 
128  ret = ff_bsf_get_packet(ctx, &in);
129  if (ret < 0)
130  return ret;
131 
132  if (!s->extradata_parsed) {
133  av_packet_move_ref(out, in);
134  av_packet_free(&in);
135  return 0;
136  }
137 
138  bytestream2_init(&gb, in->data, in->size);
139 
140  while (bytestream2_get_bytes_left(&gb)) {
141  uint32_t nalu_size = 0;
142  int nalu_type;
143  int is_irap, add_extradata, extra_size, prev_size;
144 
145  if (bytestream2_get_bytes_left(&gb) < s->length_size) {
147  goto fail;
148  }
149  for (i = 0; i < s->length_size; i++)
150  nalu_size = (nalu_size << 8) | bytestream2_get_byte(&gb);
151 
152  if (nalu_size < 2 || nalu_size > bytestream2_get_bytes_left(&gb)) {
154  goto fail;
155  }
156 
157  nalu_type = (bytestream2_peek_byte(&gb) >> 1) & 0x3f;
158 
159  /* prepend extradata to IRAP frames */
160  is_irap = nalu_type >= 16 && nalu_type <= 23;
161  add_extradata = is_irap && !got_irap;
162  extra_size = add_extradata * ctx->par_out->extradata_size;
163  got_irap |= is_irap;
164 
165  if (FFMIN(INT_MAX, SIZE_MAX) < 4ULL + nalu_size + extra_size) {
167  goto fail;
168  }
169 
170  prev_size = out->size;
171 
172  ret = av_grow_packet(out, 4 + nalu_size + extra_size);
173  if (ret < 0)
174  goto fail;
175 
176  if (extra_size)
177  memcpy(out->data + prev_size, ctx->par_out->extradata, extra_size);
178  AV_WB32(out->data + prev_size + extra_size, 1);
179  bytestream2_get_buffer(&gb, out->data + prev_size + 4 + extra_size, nalu_size);
180  }
181 
183  if (ret < 0)
184  goto fail;
185 
186 fail:
187  if (ret < 0)
189  av_packet_free(&in);
190 
191  return ret;
192 }
193 
194 static const enum AVCodecID codec_ids[] = {
196 };
197 
199  .name = "hevc_mp4toannexb",
200  .priv_data_size = sizeof(HEVCBSFContext),
203  .codec_ids = codec_ids,
204 };
av_packet_unref
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:403
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:187
init
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:31
bsf_internal.h
out
FILE * out
Definition: movenc.c:54
GetByteContext
Definition: bytestream.h:33
hevc_mp4toannexb_init
static int hevc_mp4toannexb_init(AVBSFContext *ctx)
Definition: hevc_mp4toannexb_bsf.c:98
AVBitStreamFilter::name
const char * name
Definition: bsf.h:99
av_grow_packet
int av_grow_packet(AVPacket *pkt, int grow_by)
Increase packet size, correctly zeroing padding.
Definition: avpacket.c:117
AVPacket::data
uint8_t * data
Definition: packet.h:365
AV_LOG_VERBOSE
#define AV_LOG_VERBOSE
Detailed information.
Definition: log.h:197
HEVCBSFContext::length_size
uint8_t length_size
Definition: hevc_mp4toannexb_bsf.c:36
filter
filter_frame For filters that do not use the this method is called when a frame is pushed to the filter s input It can be called at any time except in a reentrant way If the input frame is enough to produce then the filter should push the output frames on the output link immediately As an exception to the previous rule if the input frame is enough to produce several output frames then the filter needs output only at least one per link The additional frames can be left buffered in the filter
Definition: filter_design.txt:228
ff_bsf_get_packet
int ff_bsf_get_packet(AVBSFContext *ctx, AVPacket **pkt)
Called by the bitstream filters to get the next packet for filtering.
Definition: bsf.c:229
av_packet_free
void av_packet_free(AVPacket **pkt)
Free the packet, if the packet is reference counted, it will be unreferenced first.
Definition: avpacket.c:70
AVBSFContext
The bitstream filter state.
Definition: bsf.h:49
bytestream2_skip
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:168
bsf.h
fail
#define fail()
Definition: checkasm.h:134
type
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf type
Definition: writing_filters.txt:86
MIN_HEVCC_LENGTH
#define MIN_HEVCC_LENGTH
Definition: hevc_mp4toannexb_bsf.c:33
HEVCBSFContext
Definition: hevc_mp4toannexb_bsf.c:35
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:181
codec_ids
static enum AVCodecID codec_ids[]
Definition: hevc_mp4toannexb_bsf.c:194
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:257
ctx
AVFormatContext * ctx
Definition: movenc.c:48
NULL
#define NULL
Definition: coverity.c:32
HEVC_NAL_PPS
@ HEVC_NAL_PPS
Definition: hevc.h:63
ff_hevc_mp4toannexb_bsf
const AVBitStreamFilter ff_hevc_mp4toannexb_bsf
Definition: hevc_mp4toannexb_bsf.c:198
HEVC_NAL_SEI_SUFFIX
@ HEVC_NAL_SEI_SUFFIX
Definition: hevc.h:69
bytestream2_get_buffer
static av_always_inline unsigned int bytestream2_get_buffer(GetByteContext *g, uint8_t *dst, unsigned int size)
Definition: bytestream.h:267
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:459
bytestream2_get_bytes_left
static av_always_inline int bytestream2_get_bytes_left(GetByteContext *g)
Definition: bytestream.h:158
AVCodecID
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: codec_id.h:46
AV_WB32
#define AV_WB32(p, v)
Definition: intreadwrite.h:419
AVPacket::size
int size
Definition: packet.h:366
hevc_extradata_to_annexb
static int hevc_extradata_to_annexb(AVBSFContext *ctx)
Definition: hevc_mp4toannexb_bsf.c:40
av_reallocp
int av_reallocp(void *ptr, size_t size)
Allocate, reallocate, or free a block of memory through a pointer to a pointer.
Definition: mem.c:167
AV_RB32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_RB32
Definition: bytestream.h:96
FFMIN
#define FFMIN(a, b)
Definition: common.h:105
av_packet_copy_props
int av_packet_copy_props(AVPacket *dst, const AVPacket *src)
Copy only "properties" fields from src to dst.
Definition: avpacket.c:374
i
int i
Definition: input.c:407
AV_CODEC_ID_NONE
@ AV_CODEC_ID_NONE
Definition: codec_id.h:47
AV_CODEC_ID_HEVC
@ AV_CODEC_ID_HEVC
Definition: codec_id.h:223
hevc.h
avcodec.h
HEVC_NAL_VPS
@ HEVC_NAL_VPS
Definition: hevc.h:61
ret
ret
Definition: filter_design.txt:187
AV_INPUT_BUFFER_PADDING_SIZE
#define AV_INPUT_BUFFER_PADDING_SIZE
Definition: avcodec.h:192
hevc_mp4toannexb_filter
static int hevc_mp4toannexb_filter(AVBSFContext *ctx, AVPacket *out)
Definition: hevc_mp4toannexb_bsf.c:119
AVBitStreamFilter
Definition: bsf.h:98
HEVC_NAL_SPS
@ HEVC_NAL_SPS
Definition: hevc.h:62
mem.h
AVPacket
This structure stores compressed data.
Definition: packet.h:342
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:35
bytestream.h
bytestream2_init
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:137
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
AV_RB24
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_RB24
Definition: bytestream.h:97
HEVC_NAL_SEI_PREFIX
@ HEVC_NAL_SEI_PREFIX
Definition: hevc.h:68
HEVCBSFContext::extradata_parsed
int extradata_parsed
Definition: hevc_mp4toannexb_bsf.c:37
AVFormatContext::priv_data
void * priv_data
Format private data.
Definition: avformat.h:1134