FFmpeg
cbs_internal.h
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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 #ifndef AVCODEC_CBS_INTERNAL_H
20 #define AVCODEC_CBS_INTERNAL_H
21 
22 #include "avcodec.h"
23 #include "cbs.h"
24 #include "get_bits.h"
25 #include "put_bits.h"
26 
27 
28 typedef struct CodedBitstreamType {
30 
32 
33  // Split frag->data into coded bitstream units, creating the
34  // frag->units array. Fill data but not content on each unit.
35  // The header argument should be set if the fragment came from
36  // a header block, which may require different parsing for some
37  // codecs (e.g. the AVCC header in H.264).
40  int header);
41 
42  // Read the unit->data bitstream and decompose it, creating
43  // unit->content.
45  CodedBitstreamUnit *unit);
46 
47  // Write the data bitstream from unit->content into pbc.
48  // Return value AVERROR(ENOSPC) indicates that pbc was too small.
50  CodedBitstreamUnit *unit,
51  PutBitContext *pbc);
52 
53  // Read the data from all of frag->units and assemble it into
54  // a bitstream for the whole fragment.
57 
58  // Free the codec internal state.
61 
62 
63 // Helper functions for trace output.
64 
66  const char *name);
67 
69  const char *name, const int *subscripts,
70  const char *bitstring, int64_t value);
71 
72 
73 // Helper functions for read/write of common bitstream elements, including
74 // generation of trace output.
75 
77  int width, const char *name,
78  const int *subscripts, uint32_t *write_to,
79  uint32_t range_min, uint32_t range_max);
80 
82  int width, const char *name,
83  const int *subscripts, uint32_t value,
84  uint32_t range_min, uint32_t range_max);
85 
87  int width, const char *name,
88  const int *subscripts, int32_t *write_to,
89  int32_t range_min, int32_t range_max);
90 
92  int width, const char *name,
93  const int *subscripts, int32_t value,
94  int32_t range_min, int32_t range_max);
95 
96 // The largest unsigned value representable in N bits, suitable for use as
97 // range_max in the above functions.
98 #define MAX_UINT_BITS(length) ((UINT64_C(1) << (length)) - 1)
99 
100 // The largest signed value representable in N bits, suitable for use as
101 // range_max in the above functions.
102 #define MAX_INT_BITS(length) ((INT64_C(1) << ((length) - 1)) - 1)
103 
104 // The smallest signed value representable in N bits, suitable for use as
105 // range_min in the above functions.
106 #define MIN_INT_BITS(length) (-(INT64_C(1) << ((length) - 1)))
107 
108 
115 
116 
117 #endif /* AVCODEC_CBS_INTERNAL_H */
void ff_cbs_trace_syntax_element(CodedBitstreamContext *ctx, int position, const char *name, const int *subscripts, const char *bitstring, int64_t value)
Definition: cbs.c:435
int(* assemble_fragment)(CodedBitstreamContext *ctx, CodedBitstreamFragment *frag)
Definition: cbs_internal.h:55
int ff_cbs_read_signed(CodedBitstreamContext *ctx, GetBitContext *gbc, int width, const char *name, const int *subscripts, int32_t *write_to, int32_t range_min, int32_t range_max)
Definition: cbs.c:564
GLsizei GLboolean const GLfloat * value
Definition: opengl_enc.c:108
bitstream reader API header.
Coded bitstream unit structure.
Definition: cbs.h:64
void ff_cbs_trace_header(CodedBitstreamContext *ctx, const char *name)
Definition: cbs.c:426
static const uint8_t header[24]
Definition: sdr2.c:67
int(* write_unit)(CodedBitstreamContext *ctx, CodedBitstreamUnit *unit, PutBitContext *pbc)
Definition: cbs_internal.h:49
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: avcodec.h:215
void(* close)(CodedBitstreamContext *ctx)
Definition: cbs_internal.h:59
int ff_cbs_write_unsigned(CodedBitstreamContext *ctx, PutBitContext *pbc, int width, const char *name, const int *subscripts, uint32_t value, uint32_t range_min, uint32_t range_max)
Definition: cbs.c:528
const CodedBitstreamType ff_cbs_type_mpeg2
Definition: cbs_mpeg2.c:420
const CodedBitstreamType ff_cbs_type_av1
Definition: cbs_av1.c:1259
int ff_cbs_read_unsigned(CodedBitstreamContext *ctx, GetBitContext *gbc, int width, const char *name, const int *subscripts, uint32_t *write_to, uint32_t range_min, uint32_t range_max)
Definition: cbs.c:485
#define width
typedef void(APIENTRY *FF_PFNGLACTIVETEXTUREPROC)(GLenum texture)
int32_t
AVFormatContext * ctx
Definition: movenc.c:48
Libavcodec external API header.
Coded bitstream fragment structure, combining one or more units.
Definition: cbs.h:116
const CodedBitstreamType ff_cbs_type_jpeg
Definition: cbs_jpeg.c:457
Context structure for coded bitstream operations.
Definition: cbs.h:168
const CodedBitstreamType ff_cbs_type_h265
Definition: cbs_h2645.c:1511
enum AVCodecID codec_id
Definition: cbs_internal.h:29
int(* read_unit)(CodedBitstreamContext *ctx, CodedBitstreamUnit *unit)
Definition: cbs_internal.h:44
int
int(* split_fragment)(CodedBitstreamContext *ctx, CodedBitstreamFragment *frag, int header)
Definition: cbs_internal.h:38
int ff_cbs_write_signed(CodedBitstreamContext *ctx, PutBitContext *pbc, int width, const char *name, const int *subscripts, int32_t value, int32_t range_min, int32_t range_max)
Definition: cbs.c:607
const CodedBitstreamType ff_cbs_type_h264
Definition: cbs_h2645.c:1498
const CodedBitstreamType ff_cbs_type_vp9
Definition: cbs_vp9.c:640
const char * name
Definition: opengl_enc.c:102
bitstream writer API