FFmpeg
video_enc_params.c
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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
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8  *
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12  * Lesser General Public License for more details.
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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 <limits.h>
20 #include <stddef.h>
21 #include <stdint.h>
22 
23 #include "buffer.h"
24 #include "common.h"
25 #include "frame.h"
26 #include "mem.h"
27 #include "video_enc_params.h"
28 
30  unsigned int nb_blocks, size_t *out_size)
31 {
32  AVVideoEncParams *par;
33  size_t size;
34 
35  size = sizeof(*par);
36  if (nb_blocks > (SIZE_MAX - size) / sizeof(AVVideoBlockParams))
37  return NULL;
38  size += sizeof(AVVideoBlockParams) * nb_blocks;
39 
40  par = av_mallocz(size);
41  if (!par)
42  return NULL;
43 
44  par->type = type;
45  par->nb_blocks = nb_blocks;
46  par->block_size = sizeof(AVVideoBlockParams);
47  par->blocks_offset = sizeof(*par);
48 
49  if (out_size)
50  *out_size = size;
51 
52  return par;
53 }
54 
57  unsigned int nb_blocks)
58 {
59  AVBufferRef *buf;
60  AVVideoEncParams *par;
61  size_t size;
62 
63  par = av_video_enc_params_alloc(type, nb_blocks, &size);
64  if (!par)
65  return NULL;
66  if (size > INT_MAX) {
67  av_free(par);
68  return NULL;
69  }
70  buf = av_buffer_create((uint8_t *)par, size, NULL, NULL, 0);
71  if (!buf) {
72  av_freep(&par);
73  return NULL;
74  }
75 
77  av_buffer_unref(&buf);
78  return NULL;
79  }
80 
81  return par;
82 }
AVVideoEncParams::blocks_offset
size_t blocks_offset
Offset in bytes from the beginning of this structure at which the array of blocks starts.
Definition: video_enc_params.h:86
out_size
int out_size
Definition: movenc.c:55
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:318
av_buffer_create
AVBufferRef * av_buffer_create(uint8_t *data, buffer_size_t size, void(*free)(void *opaque, uint8_t *data), void *opaque, int flags)
Create an AVBuffer from an existing array.
Definition: buffer.c:29
av_video_enc_params_alloc
AVVideoEncParams * av_video_enc_params_alloc(enum AVVideoEncParamsType type, unsigned int nb_blocks, size_t *out_size)
Allocates memory for AVVideoEncParams of the given type, plus an array of.
Definition: video_enc_params.c:29
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
AVVideoEncParams
Video encoding parameters for a given frame.
Definition: video_enc_params.h:73
AVVideoEncParamsType
AVVideoEncParamsType
Definition: video_enc_params.h:28
limits.h
AVVideoEncParams::type
enum AVVideoEncParamsType type
Type of the parameters (the codec they are used with).
Definition: video_enc_params.h:95
NULL
#define NULL
Definition: coverity.c:32
av_buffer_unref
void av_buffer_unref(AVBufferRef **buf)
Free a given reference and automatically free the buffer if there are no more references to it.
Definition: buffer.c:125
av_frame_new_side_data_from_buf
AVFrameSideData * av_frame_new_side_data_from_buf(AVFrame *frame, enum AVFrameSideDataType type, AVBufferRef *buf)
Add a new side data to a frame from an existing AVBufferRef.
Definition: frame.c:694
AVVideoEncParams::block_size
size_t block_size
Definition: video_enc_params.h:90
av_video_enc_params_create_side_data
AVVideoEncParams * av_video_enc_params_create_side_data(AVFrame *frame, enum AVVideoEncParamsType type, unsigned int nb_blocks)
Allocates memory for AVEncodeInfoFrame plus an array of.
Definition: video_enc_params.c:56
size
int size
Definition: twinvq_data.h:10344
AVVideoEncParams::nb_blocks
unsigned int nb_blocks
Number of blocks in the array.
Definition: video_enc_params.h:81
frame.h
buffer.h
common.h
uint8_t
uint8_t
Definition: audio_convert.c:194
AVVideoBlockParams
Data structure for storing block-level encoding information.
Definition: video_enc_params.h:120
av_mallocz
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:237
frame
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:264
AV_FRAME_DATA_VIDEO_ENC_PARAMS
@ AV_FRAME_DATA_VIDEO_ENC_PARAMS
Encoding parameters for a video frame, as described by AVVideoEncParams.
Definition: frame.h:186
mem.h
AVBufferRef
A reference to a data buffer.
Definition: buffer.h:84
av_free
#define av_free(p)
Definition: tableprint_vlc.h:34
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:35
video_enc_params.h