FFmpeg
cbs_bsf.h
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18 
19 #ifndef AVCODEC_CBS_BSF_H
20 #define AVCODEC_CBS_BSF_H
21 
22 #include "cbs.h"
23 
24 
25 typedef struct CBSBSFType {
27 
28  // Name of a frame fragment in this codec (e.g. "access unit",
29  // "temporal unit").
30  const char *fragment_name;
31 
32  // Name of a unit for this BSF, for use in error messages (e.g.
33  // "NAL unit", "OBU").
34  const char *unit_name;
35 
36  // Update the content of a fragment with whatever metadata changes
37  // are desired. The associated AVPacket is provided so that any side
38  // data associated with the fragment can be inspected or edited. If
39  // pkt is NULL, then an extradata header fragment is being updated.
42 } CBSBSFType;
43 
44 // Common structure for all generic CBS BSF users. An instance of this
45 // structure must be the first member of the BSF private context (to be
46 // pointed to by AVBSFContext.priv_data).
47 typedef struct CBSBSFContext {
48  const AVClass *class;
49  const CBSBSFType *type;
50 
55 
56 /**
57  * Initialise generic CBS BSF setup.
58  *
59  * Creates the input and output CBS instances, and applies the filter to
60  * the extradata on the input codecpar if any is present.
61  *
62  * Since it calls the update_fragment() function immediately to deal with
63  * extradata, this should be called after any codec-specific setup is done
64  * (probably at the end of the AVBitStreamFilter.init function).
65  */
67 
68 /**
69  * Close a generic CBS BSF instance.
70  *
71  * If no other deinitialisation is required then this function can be used
72  * directly as AVBitStreamFilter.close.
73  */
75 
76 /**
77  * Filter operation for CBS BSF.
78  *
79  * Reads the input packet into a CBS fragment, calls update_fragment() on
80  * it, then writes the result to an output packet. If the input packet
81  * has AV_PKT_DATA_NEW_EXTRADATA side-data associated with it then it does
82  * the same thing to that new extradata to form the output side-data first.
83  *
84  * If the BSF does not do anything else then this function can be used
85  * directly as AVBitStreamFilter.filter.
86  */
88 
89 
90 // Options for element manipulation.
91 enum {
92  // Pass this element through unchanged.
94  // Insert this element, replacing any existing instances of it.
95  // Associated values may be provided explicitly (as addtional options)
96  // or implicitly (either as side data or deduced from other parts of
97  // the stream).
99  // Remove this element if it appears in the stream.
101  // Extract this element to side data, so that further manipulation
102  // can happen elsewhere.
104 };
105 
106 #define BSF_ELEMENT_OPTIONS_PIR(name, help, field, opt_flags) \
107  { name, help, OFFSET(field), AV_OPT_TYPE_INT, \
108  { .i64 = BSF_ELEMENT_PASS }, \
109  BSF_ELEMENT_PASS, BSF_ELEMENT_REMOVE, opt_flags, name }, \
110  { "pass", NULL, 0, AV_OPT_TYPE_CONST, \
111  { .i64 = BSF_ELEMENT_PASS }, .flags = opt_flags, .unit = name }, \
112  { "insert", NULL, 0, AV_OPT_TYPE_CONST, \
113  { .i64 = BSF_ELEMENT_INSERT }, .flags = opt_flags, .unit = name }, \
114  { "remove", NULL, 0, AV_OPT_TYPE_CONST, \
115  { .i64 = BSF_ELEMENT_REMOVE }, .flags = opt_flags, .unit = name }
116 
117 #define BSF_ELEMENT_OPTIONS_PIRE(name, help, field, opt_flags) \
118  { name, help, OFFSET(field), AV_OPT_TYPE_INT, \
119  { .i64 = BSF_ELEMENT_PASS }, \
120  BSF_ELEMENT_PASS, BSF_ELEMENT_EXTRACT, opt_flags, name }, \
121  { "pass", NULL, 0, AV_OPT_TYPE_CONST, \
122  { .i64 = BSF_ELEMENT_PASS }, .flags = opt_flags, .unit = name }, \
123  { "insert", NULL, 0, AV_OPT_TYPE_CONST, \
124  { .i64 = BSF_ELEMENT_INSERT }, .flags = opt_flags, .unit = name }, \
125  { "remove", NULL, 0, AV_OPT_TYPE_CONST, \
126  { .i64 = BSF_ELEMENT_REMOVE }, .flags = opt_flags, .unit = name }, \
127  { "extract", NULL, 0, AV_OPT_TYPE_CONST, \
128  { .i64 = BSF_ELEMENT_EXTRACT }, .flags = opt_flags, .unit = name } \
129 
130 
131 #endif /* AVCODEC_CBS_BSF_H */
int ff_cbs_bsf_generic_init(AVBSFContext *bsf, const CBSBSFType *type)
Initialise generic CBS BSF setup.
Definition: cbs_bsf.c:112
enum AVCodecID codec_id
Definition: cbs_bsf.h:26
The bitstream filter state.
Definition: bsf.h:49
GLint GLenum type
Definition: opengl_enc.c:104
const char * fragment_name
Definition: cbs_bsf.h:30
static AVPacket pkt
const CBSBSFType * type
Definition: cbs_bsf.h:49
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: codec_id.h:46
const char * unit_name
Definition: cbs_bsf.h:34
int(* update_fragment)(AVBSFContext *bsf, AVPacket *pkt, CodedBitstreamFragment *frag)
Definition: cbs_bsf.h:40
Coded bitstream fragment structure, combining one or more units.
Definition: cbs.h:118
void ff_cbs_bsf_generic_close(AVBSFContext *bsf)
Close a generic CBS BSF instance.
Definition: cbs_bsf.c:152
Describe the class of an AVClass context structure.
Definition: log.h:67
Context structure for coded bitstream operations.
Definition: cbs.h:170
CodedBitstreamContext * output
Definition: cbs_bsf.h:52
int
CodedBitstreamContext * input
Definition: cbs_bsf.h:51
int ff_cbs_bsf_generic_filter(AVBSFContext *bsf, AVPacket *pkt)
Filter operation for CBS BSF.
Definition: cbs_bsf.c:63
This structure stores compressed data.
Definition: packet.h:340
CodedBitstreamFragment fragment
Definition: cbs_bsf.h:53