FFmpeg
encode.h
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1 /*
2  * generic encoding-related 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_ENCODE_H
22 #define AVCODEC_ENCODE_H
23 
24 #include "libavutil/frame.h"
25 
26 #include "avcodec.h"
27 #include "packet.h"
28 
29 /**
30  * Called by encoders to get the next frame for encoding.
31  *
32  * @param frame An empty frame to be filled with data.
33  * @return 0 if a new reference has been successfully written to frame
34  * AVERROR(EAGAIN) if no data is currently available
35  * AVERROR_EOF if end of stream has been reached, so no more data
36  * will be available
37  */
39 
40 /**
41  * Get a buffer for a packet. This is a wrapper around
42  * AVCodecContext.get_encode_buffer() and should be used instead calling get_encode_buffer()
43  * directly.
44  */
45 int ff_get_encode_buffer(AVCodecContext *avctx, AVPacket *avpkt, int64_t size, int flags);
46 
47 /**
48  * Check AVPacket size and allocate data.
49  *
50  * Encoders supporting AVCodec.encode2() can use this as a convenience to
51  * obtain a big enough buffer for the encoded bitstream.
52  *
53  * @param avctx the AVCodecContext of the encoder
54  * @param avpkt The AVPacket: on success, avpkt->data will point to a buffer
55  * of size at least `size`; the packet will not be refcounted.
56  * This packet must be initially blank.
57  * @param size an upper bound of the size of the packet to encode
58  * @return non negative on success, negative error code on failure
59  */
60 int ff_alloc_packet(AVCodecContext *avctx, AVPacket *avpkt, int64_t size);
61 
62 /*
63  * Perform encoder initialization and validation.
64  * Called when opening the encoder, before the AVCodec.init() call.
65  */
67 
68 #endif /* AVCODEC_ENCODE_H */
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:303
ff_encode_preinit
int ff_encode_preinit(AVCodecContext *avctx)
Definition: encode.c:412
size
int size
Definition: twinvq_data.h:10344
frame.h
packet.h
ff_encode_get_frame
int ff_encode_get_frame(AVCodecContext *avctx, AVFrame *frame)
Called by encoders to get the next frame for encoding.
Definition: encode.c:156
avcodec.h
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
AVCodecContext
main external API structure.
Definition: avcodec.h:384
ff_alloc_packet
int ff_alloc_packet(AVCodecContext *avctx, AVPacket *avpkt, int64_t size)
Check AVPacket size and allocate data.
Definition: encode.c:33
ff_get_encode_buffer
int ff_get_encode_buffer(AVCodecContext *avctx, AVPacket *avpkt, int64_t size, int flags)
Get a buffer for a packet.
Definition: encode.c:77
AVPacket
This structure stores compressed data.
Definition: packet.h:342
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561