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h2645_parse.h
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1 /*
2  * H.264/HEVC common parsing 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 #ifndef AVCODEC_H2645_PARSE_H
22 #define AVCODEC_H2645_PARSE_H
23 
24 #include <stdint.h>
25 
26 #include "avcodec.h"
27 #include "get_bits.h"
28 
29 #define MAX_MBPAIR_SIZE (256*1024) // a tighter bound could be calculated if someone cares about a few bytes
30 
31 typedef struct H2645NAL {
33 
34  int size;
35  const uint8_t *data;
36 
37  /**
38  * Size, in bits, of just the data, excluding the stop bit and any trailing
39  * padding. I.e. what HEVC calls SODB.
40  */
41  int size_bits;
42 
43  int raw_size;
44  const uint8_t *raw_data;
45 
47 
48  /**
49  * NAL unit type
50  */
51  int type;
52 
53  /**
54  * HEVC only, nuh_temporal_id_plus_1 - 1
55  */
57 
61  /**
62  * H.264 only, nal_ref_idc
63  */
64  int ref_idc;
65 } H2645NAL;
66 
67 typedef struct H2645RBSP {
71 } H2645RBSP;
72 
73 /* an input packet split into unescaped NAL units */
74 typedef struct H2645Packet {
77  int nb_nals;
79 } H2645Packet;
80 
81 /**
82  * Extract the raw (unescaped) bitstream.
83  */
84 int ff_h2645_extract_rbsp(const uint8_t *src, int length, H2645RBSP *rbsp,
85  H2645NAL *nal, int small_padding);
86 
87 /**
88  * Split an input packet into NAL units.
89  */
91  void *logctx, int is_nalff, int nal_length_size,
92  enum AVCodecID codec_id, int small_padding);
93 
94 /**
95  * Free all the allocated memory in the packet.
96  */
98 
99 static inline int get_nalsize(int nal_length_size, const uint8_t *buf,
100  int buf_size, int *buf_index, void *logctx)
101 {
102  int i, nalsize = 0;
103 
104  if (*buf_index >= buf_size - nal_length_size) {
105  // the end of the buffer is reached, refill it
106  return AVERROR(EAGAIN);
107  }
108 
109  for (i = 0; i < nal_length_size; i++)
110  nalsize = ((unsigned)nalsize << 8) | buf[(*buf_index)++];
111  if (nalsize <= 0 || nalsize > buf_size - *buf_index) {
112  av_log(logctx, AV_LOG_ERROR,
113  "Invalid NAL unit size (%d > %d).\n", nalsize, buf_size - *buf_index);
114  return AVERROR_INVALIDDATA;
115  }
116  return nalsize;
117 }
118 
119 #endif /* AVCODEC_H2645_PARSE_H */
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
int size
Definition: h2645_parse.h:34
static AVPacket pkt
#define src
Definition: vp8dsp.c:254
int size_bits
Size, in bits, of just the data, excluding the stop bit and any trailing padding. ...
Definition: h2645_parse.h:41
int ff_h2645_extract_rbsp(const uint8_t *src, int length, H2645RBSP *rbsp, H2645NAL *nal, int small_padding)
Extract the raw (unescaped) bitstream.
Definition: h2645_parse.c:33
int skipped_bytes_pos_size
Definition: h2645_parse.h:59
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)
Split an input packet into NAL units.
Definition: h2645_parse.c:263
uint8_t
bitstream reader API header.
#define av_log(a,...)
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: avcodec.h:215
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
int * skipped_bytes_pos
Definition: h2645_parse.h:60
#define AVERROR(e)
Definition: error.h:43
void ff_h2645_packet_uninit(H2645Packet *pkt)
Free all the allocated memory in the packet.
Definition: h2645_parse.c:386
GLsizei GLsizei * length
Definition: opengl_enc.c:115
int raw_size
Definition: h2645_parse.h:43
static int get_nalsize(int nal_length_size, const uint8_t *buf, int buf_size, int *buf_index, void *logctx)
Definition: h2645_parse.h:99
enum AVCodecID codec_id
Definition: vaapi_decode.c:236
int ref_idc
H.264 only, nal_ref_idc.
Definition: h2645_parse.h:64
int type
NAL unit type.
Definition: h2645_parse.h:51
Libavcodec external API header.
int nals_allocated
Definition: h2645_parse.h:78
const uint8_t * data
Definition: h2645_parse.h:35
void * buf
Definition: avisynth_c.h:690
int rbsp_buffer_size
Definition: h2645_parse.h:70
int rbsp_buffer_alloc_size
Definition: h2645_parse.h:69
uint8_t * rbsp_buffer
Definition: h2645_parse.h:68
H2645RBSP rbsp
Definition: h2645_parse.h:76
int skipped_bytes
Definition: h2645_parse.h:58
GetBitContext gb
Definition: h2645_parse.h:46
const uint8_t * raw_data
Definition: h2645_parse.h:44
H2645NAL * nals
Definition: h2645_parse.h:75
int temporal_id
HEVC only, nuh_temporal_id_plus_1 - 1.
Definition: h2645_parse.h:56
uint8_t * rbsp_buffer
Definition: h2645_parse.h:32