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1 /*
2  * generic decoding-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
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  */
24 #include "libavutil/buffer.h"
25 #include "libavutil/frame.h"
26 #include "libavutil/hwcontext.h"
28 #include "avcodec.h"
30 /**
31  * This struct stores per-frame lavc-internal data and is attached to it via
32  * private_ref.
33  */
34 typedef struct FrameDecodeData {
35  /**
36  * The callback to perform some delayed processing on the frame right
37  * before it is returned to the caller.
38  *
39  * @note This code is called at some unspecified point after the frame is
40  * returned from the decoder's decode/receive_frame call. Therefore it cannot rely
41  * on AVCodecContext being in any specific state, so it does not get to
42  * access AVCodecContext directly at all. All the state it needs must be
43  * stored in the post_process_opaque object.
44  */
45  int (*post_process)(void *logctx, AVFrame *frame);
47  void (*post_process_opaque_free)(void *opaque);
49  /**
50  * Per-frame private data for hwaccels.
51  */
52  void *hwaccel_priv;
53  void (*hwaccel_priv_free)(void *priv);
56 /**
57  * Called by decoders to get the next packet for decoding.
58  *
59  * @param pkt An empty packet to be filled with data.
60  * @return 0 if a new reference has been successfully written to pkt
61  * AVERROR(EAGAIN) if no data is currently available
62  * AVERROR_EOF if and end of stream has been reached, so no more data
63  * will be available
64  */
71 /**
72  * Make sure avctx.hw_frames_ctx is set. If it's not set, the function will
73  * try to allocate it from hw_device_ctx. If that is not possible, an error
74  * message is printed, and an error code is returned.
75  */
77  enum AVHWDeviceType dev_type);
81 #endif /* AVCODEC_DECODE_H */
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
void(* hwaccel_priv_free)(void *priv)
Definition: decode.h:53
static AVPacket pkt
void * post_process_opaque
Definition: decode.h:46
reference-counted frame API
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
int(* post_process)(void *logctx, AVFrame *frame)
The callback to perform some delayed processing on the frame right before it is returned to the calle...
Definition: decode.h:45
void(* post_process_opaque_free)(void *opaque)
Definition: decode.h:47
Libavcodec external API header.
main external API structure.
Definition: avcodec.h:1621
void ff_decode_bsfs_uninit(AVCodecContext *avctx)
Definition: decode.c:2060
refcounted data buffer API
int ff_attach_decode_data(AVFrame *frame)
Definition: decode.c:1882
int ff_decode_get_packet(AVCodecContext *avctx, AVPacket *pkt)
Called by decoders to get the next packet for decoding.
Definition: decode.c:328
This struct stores per-frame lavc-internal data and is attached to it via private_ref.
Definition: decode.h:34
int ff_decode_get_hw_frames_ctx(AVCodecContext *avctx, enum AVHWDeviceType dev_type)
Make sure avctx.hw_frames_ctx is set.
Definition: decode.c:1221
Definition: hwcontext.h:27
void * hwaccel_priv
Per-frame private data for hwaccels.
Definition: decode.h:52
This structure stores compressed data.
Definition: avcodec.h:1510
int ff_decode_bsfs_init(AVCodecContext *avctx)
Definition: decode.c:185