FFmpeg
hevc_parse.c
Go to the documentation of this file.
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 #include "bytestream.h"
20 #include "h2645_parse.h"
21 #include "hevc.h"
22 #include "hevc_parse.h"
23 
24 static int hevc_decode_nal_units(const uint8_t *buf, int buf_size, HEVCParamSets *ps,
25  HEVCSEI *sei, int is_nalff, int nal_length_size,
26  int err_recognition, int apply_defdispwin, void *logctx)
27 {
28  int i;
29  int ret = 0;
30  H2645Packet pkt = { 0 };
31 
32  ret = ff_h2645_packet_split(&pkt, buf, buf_size, logctx, is_nalff,
33  nal_length_size, AV_CODEC_ID_HEVC, 1, 0);
34  if (ret < 0) {
35  goto done;
36  }
37 
38  for (i = 0; i < pkt.nb_nals; i++) {
39  H2645NAL *nal = &pkt.nals[i];
40  if (nal->nuh_layer_id > 0)
41  continue;
42 
43  /* ignore everything except parameter sets and VCL NALUs */
44  switch (nal->type) {
45  case HEVC_NAL_VPS:
46  ret = ff_hevc_decode_nal_vps(&nal->gb, logctx, ps);
47  if (ret < 0)
48  goto done;
49  break;
50  case HEVC_NAL_SPS:
51  ret = ff_hevc_decode_nal_sps(&nal->gb, logctx, ps, apply_defdispwin);
52  if (ret < 0)
53  goto done;
54  break;
55  case HEVC_NAL_PPS:
56  ret = ff_hevc_decode_nal_pps(&nal->gb, logctx, ps);
57  if (ret < 0)
58  goto done;
59  break;
62  ret = ff_hevc_decode_nal_sei(&nal->gb, logctx, sei, ps, nal->type);
63  if (ret < 0)
64  goto done;
65  break;
66  default:
67  av_log(logctx, AV_LOG_VERBOSE, "Ignoring NAL type %d in extradata\n", nal->type);
68  break;
69  }
70  }
71 
72 done:
74  if (err_recognition & AV_EF_EXPLODE)
75  return ret;
76 
77  return 0;
78 }
79 
80 int ff_hevc_decode_extradata(const uint8_t *data, int size, HEVCParamSets *ps,
81  HEVCSEI *sei, int *is_nalff, int *nal_length_size,
82  int err_recognition, int apply_defdispwin, void *logctx)
83 {
84  int ret = 0;
85  GetByteContext gb;
86 
87  bytestream2_init(&gb, data, size);
88 
89  if (size > 3 && (data[0] || data[1] || data[2] > 1)) {
90  /* It seems the extradata is encoded as hvcC format.
91  * Temporarily, we support configurationVersion==0 until 14496-15 3rd
92  * is finalized. When finalized, configurationVersion will be 1 and we
93  * can recognize hvcC by checking if avctx->extradata[0]==1 or not. */
94  int i, j, num_arrays, nal_len_size;
95 
96  *is_nalff = 1;
97 
98  bytestream2_skip(&gb, 21);
99  nal_len_size = (bytestream2_get_byte(&gb) & 3) + 1;
100  num_arrays = bytestream2_get_byte(&gb);
101 
102  /* nal units in the hvcC always have length coded with 2 bytes,
103  * so put a fake nal_length_size = 2 while parsing them */
104  *nal_length_size = 2;
105 
106  /* Decode nal units from hvcC. */
107  for (i = 0; i < num_arrays; i++) {
108  int type = bytestream2_get_byte(&gb) & 0x3f;
109  int cnt = bytestream2_get_be16(&gb);
110 
111  for (j = 0; j < cnt; j++) {
112  // +2 for the nal size field
113  int nalsize = bytestream2_peek_be16(&gb) + 2;
114  if (bytestream2_get_bytes_left(&gb) < nalsize) {
115  av_log(logctx, AV_LOG_ERROR,
116  "Invalid NAL unit size in extradata.\n");
117  return AVERROR_INVALIDDATA;
118  }
119 
120  ret = hevc_decode_nal_units(gb.buffer, nalsize, ps, sei, *is_nalff,
121  *nal_length_size, err_recognition, apply_defdispwin,
122  logctx);
123  if (ret < 0) {
124  av_log(logctx, AV_LOG_ERROR,
125  "Decoding nal unit %d %d from hvcC failed\n",
126  type, i);
127  return ret;
128  }
129  bytestream2_skip(&gb, nalsize);
130  }
131  }
132 
133  /* Now store right nal length size, that will be used to parse
134  * all other nals */
135  *nal_length_size = nal_len_size;
136  } else {
137  *is_nalff = 0;
138  ret = hevc_decode_nal_units(data, size, ps, sei, *is_nalff, *nal_length_size,
139  err_recognition, apply_defdispwin, logctx);
140  if (ret < 0)
141  return ret;
142  }
143 
144  return ret;
145 }
AV_EF_EXPLODE
#define AV_EF_EXPLODE
abort decoding on minor error detection
Definition: defs.h:51
h2645_parse.h
GetByteContext
Definition: bytestream.h:33
H2645NAL::nuh_layer_id
int nuh_layer_id
Definition: h2645_parse.h:67
ff_h2645_packet_uninit
void ff_h2645_packet_uninit(H2645Packet *pkt)
Free all the allocated memory in the packet.
Definition: h2645_parse.c:528
data
const char data[16]
Definition: mxf.c:146
AV_LOG_VERBOSE
#define AV_LOG_VERBOSE
Detailed information.
Definition: log.h:196
bytestream2_skip
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:168
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
hevc_decode_nal_units
static int hevc_decode_nal_units(const uint8_t *buf, int buf_size, HEVCParamSets *ps, HEVCSEI *sei, int is_nalff, int nal_length_size, int err_recognition, int apply_defdispwin, void *logctx)
Definition: hevc_parse.c:24
ff_hevc_decode_nal_sei
int ff_hevc_decode_nal_sei(GetBitContext *gb, void *logctx, HEVCSEI *s, const HEVCParamSets *ps, enum HEVCNALUnitType type)
Definition: hevc_sei.c:278
hevc_parse.h
pkt
AVPacket * pkt
Definition: movenc.c:59
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
GetByteContext::buffer
const uint8_t * buffer
Definition: bytestream.h:34
HEVCSEI
Definition: hevc_sei.h:95
H2645NAL::type
int type
NAL unit type.
Definition: h2645_parse.h:52
HEVC_NAL_PPS
@ HEVC_NAL_PPS
Definition: hevc.h:63
HEVC_NAL_SEI_SUFFIX
@ HEVC_NAL_SEI_SUFFIX
Definition: hevc.h:69
ff_hevc_decode_extradata
int ff_hevc_decode_extradata(const uint8_t *data, int size, HEVCParamSets *ps, HEVCSEI *sei, int *is_nalff, int *nal_length_size, int err_recognition, int apply_defdispwin, void *logctx)
Definition: hevc_parse.c:80
sei
static int FUNC() sei(CodedBitstreamContext *ctx, RWContext *rw, H264RawSEI *current)
Definition: cbs_h264_syntax_template.c:825
bytestream2_get_bytes_left
static av_always_inline int bytestream2_get_bytes_left(GetByteContext *g)
Definition: bytestream.h:158
ff_hevc_decode_nal_sps
int ff_hevc_decode_nal_sps(GetBitContext *gb, AVCodecContext *avctx, HEVCParamSets *ps, int apply_defdispwin)
Definition: hevc_ps.c:1190
size
int size
Definition: twinvq_data.h:10344
H2645NAL::gb
GetBitContext gb
Definition: h2645_parse.h:47
H2645NAL
Definition: h2645_parse.h:34
ff_hevc_decode_nal_vps
int ff_hevc_decode_nal_vps(GetBitContext *gb, AVCodecContext *avctx, HEVCParamSets *ps)
Definition: hevc_ps.c:436
ff_h2645_packet_split
int ff_h2645_packet_split(H2645Packet *pkt, const uint8_t *buf, int length, void *logctx, int is_nalff, int nal_length_size, enum AVCodecID codec_id, int small_padding, int use_ref)
Split an input packet into NAL units.
Definition: h2645_parse.c:396
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
AV_CODEC_ID_HEVC
@ AV_CODEC_ID_HEVC
Definition: codec_id.h:226
hevc.h
HEVC_NAL_VPS
@ HEVC_NAL_VPS
Definition: hevc.h:61
ret
ret
Definition: filter_design.txt:187
HEVC_NAL_SPS
@ HEVC_NAL_SPS
Definition: hevc.h:62
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:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
ff_hevc_decode_nal_pps
int ff_hevc_decode_nal_pps(GetBitContext *gb, AVCodecContext *avctx, HEVCParamSets *ps)
Definition: hevc_ps.c:1439
HEVC_NAL_SEI_PREFIX
@ HEVC_NAL_SEI_PREFIX
Definition: hevc.h:68
H2645Packet
Definition: h2645_parse.h:82
HEVCParamSets
Definition: hevc_ps.h:314