FFmpeg
hwaccel_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 /**
20  * Header providing the internals of AVHWAccel.
21  */
22 
23 #ifndef AVCODEC_HWACCEL_INTERNAL_H
24 #define AVCODEC_HWACCEL_INTERNAL_H
25 
26 #include <stdint.h>
27 
28 #include "avcodec.h"
29 #include "refstruct.h"
30 
31 #define HWACCEL_CAP_ASYNC_SAFE (1 << 0)
32 #define HWACCEL_CAP_THREAD_SAFE (1 << 1)
33 
34 typedef struct FFHWAccel {
35  /**
36  * The public AVHWAccel. See avcodec.h for it.
37  */
39 
40  /**
41  * Allocate a custom buffer
42  */
44 
45  /**
46  * Called at the beginning of each frame or field picture.
47  *
48  * Meaningful frame information (codec specific) is guaranteed to
49  * be parsed at this point. This function is mandatory.
50  *
51  * Note that buf can be NULL along with buf_size set to 0.
52  * Otherwise, this means the whole frame is available at this point.
53  *
54  * @param avctx the codec context
55  * @param buf the frame data buffer base
56  * @param buf_size the size of the frame in bytes
57  * @return zero if successful, a negative value otherwise
58  */
59  int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
60 
61  /**
62  * Callback for parameter data (SPS/PPS/VPS etc).
63  *
64  * Useful for hardware decoders which keep persistent state about the
65  * video parameters, and need to receive any changes to update that state.
66  *
67  * @param avctx the codec context
68  * @param type the nal unit type
69  * @param buf the nal unit data buffer
70  * @param buf_size the size of the nal unit in bytes
71  * @return zero if successful, a negative value otherwise
72  */
73  int (*decode_params)(AVCodecContext *avctx, int type, const uint8_t *buf, uint32_t buf_size);
74 
75  /**
76  * Callback for each slice.
77  *
78  * Meaningful slice information (codec specific) is guaranteed to
79  * be parsed at this point. This function is mandatory.
80  *
81  * @param avctx the codec context
82  * @param buf the slice data buffer base
83  * @param buf_size the size of the slice in bytes
84  * @return zero if successful, a negative value otherwise
85  */
86  int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
87 
88  /**
89  * Called at the end of each frame or field picture.
90  *
91  * The whole picture is parsed at this point and can now be sent
92  * to the hardware accelerator. This function is mandatory.
93  *
94  * @param avctx the codec context
95  * @return zero if successful, a negative value otherwise
96  */
98 
99  /**
100  * Size of per-frame hardware accelerator private data.
101  *
102  * Private data is allocated with av_mallocz() before
103  * AVCodecContext.get_buffer() and deallocated after
104  * AVCodecContext.release_buffer().
105  */
107 
108  /**
109  * Size of the private data to allocate in
110  * AVCodecInternal.hwaccel_priv_data.
111  */
113 
114  /**
115  * Internal hwaccel capabilities.
116  */
118 
119  /**
120  * Initialize the hwaccel private data.
121  *
122  * This will be called from ff_get_format(), after hwaccel and
123  * hwaccel_context are set and the hwaccel private data in AVCodecInternal
124  * is allocated.
125  */
126  int (*init)(AVCodecContext *avctx);
127 
128  /**
129  * Uninitialize the hwaccel private data.
130  *
131  * This will be called from get_format() or ff_codec_close(), after hwaccel
132  * and hwaccel_context are already uninitialized.
133  */
135 
136  /**
137  * Fill the given hw_frames context with current codec parameters. Called
138  * from get_format. Refer to avcodec_get_hw_frames_parameters() for
139  * details.
140  *
141  * This CAN be called before AVHWAccel.init is called, and you must assume
142  * that avctx->hwaccel_priv_data is invalid.
143  */
144  int (*frame_params)(AVCodecContext *avctx, AVBufferRef *hw_frames_ctx);
145 
146  /**
147  * Copy necessary context variables from a previous thread context to the current one.
148  * For thread-safe hwaccels only.
149  */
151 
152  /**
153  * Callback to free the hwaccel-specific frame data.
154  *
155  * @param hwctx a pointer to an AVHWDeviceContext.
156  * @param data the per-frame hardware accelerator private data to be freed.
157  */
158  void (*free_frame_priv)(FFRefStructOpaque hwctx, void *data);
159 
160  /**
161  * Callback to flush the hwaccel state.
162  */
163  void (*flush)(AVCodecContext *avctx);
164 } FFHWAccel;
165 
166 static inline const FFHWAccel *ffhwaccel(const AVHWAccel *codec)
167 {
168  return (const FFHWAccel*)codec;
169 }
170 
171 #define FF_HW_CALL(avctx, function, ...) \
172  (ffhwaccel((avctx)->hwaccel)->function((avctx), __VA_ARGS__))
173 
174 #define FF_HW_SIMPLE_CALL(avctx, function) \
175  (ffhwaccel((avctx)->hwaccel)->function(avctx))
176 
177 #define FF_HW_HAS_CB(avctx, function) \
178  ((avctx)->hwaccel && ffhwaccel((avctx)->hwaccel)->function)
179 
180 #endif /* AVCODEC_HWACCEL_INTERNAL */
FFHWAccel::p
AVHWAccel p
The public AVHWAccel.
Definition: hwaccel_internal.h:38
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:374
FFHWAccel::frame_params
int(* frame_params)(AVCodecContext *avctx, AVBufferRef *hw_frames_ctx)
Fill the given hw_frames context with current codec parameters.
Definition: hwaccel_internal.h:144
data
const char data[16]
Definition: mxf.c:148
FFHWAccel::flush
void(* flush)(AVCodecContext *avctx)
Callback to flush the hwaccel state.
Definition: hwaccel_internal.h:163
FFRefStructOpaque
RefStruct is an API for creating reference-counted objects with minimal overhead.
Definition: refstruct.h:58
AVHWAccel
Definition: avcodec.h:2089
FFHWAccel::alloc_frame
int(* alloc_frame)(AVCodecContext *avctx, AVFrame *frame)
Allocate a custom buffer.
Definition: hwaccel_internal.h:43
FFHWAccel
Definition: hwaccel_internal.h:34
FFHWAccel::end_frame
int(* end_frame)(AVCodecContext *avctx)
Called at the end of each frame or field picture.
Definition: hwaccel_internal.h:97
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
refstruct.h
FFHWAccel::start_frame
int(* start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size)
Called at the beginning of each frame or field picture.
Definition: hwaccel_internal.h:59
FFHWAccel::frame_priv_data_size
int frame_priv_data_size
Size of per-frame hardware accelerator private data.
Definition: hwaccel_internal.h:106
FFHWAccel::priv_data_size
int priv_data_size
Size of the private data to allocate in AVCodecInternal.hwaccel_priv_data.
Definition: hwaccel_internal.h:112
FFHWAccel::decode_params
int(* decode_params)(AVCodecContext *avctx, int type, const uint8_t *buf, uint32_t buf_size)
Callback for parameter data (SPS/PPS/VPS etc).
Definition: hwaccel_internal.h:73
FFHWAccel::init
int(* init)(AVCodecContext *avctx)
Initialize the hwaccel private data.
Definition: hwaccel_internal.h:126
FFHWAccel::uninit
int(* uninit)(AVCodecContext *avctx)
Uninitialize the hwaccel private data.
Definition: hwaccel_internal.h:134
FFHWAccel::free_frame_priv
void(* free_frame_priv)(FFRefStructOpaque hwctx, void *data)
Callback to free the hwaccel-specific frame data.
Definition: hwaccel_internal.h:158
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:445
ffhwaccel
static const FFHWAccel * ffhwaccel(const AVHWAccel *codec)
Definition: hwaccel_internal.h:166
FFHWAccel::decode_slice
int(* decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size)
Callback for each slice.
Definition: hwaccel_internal.h:86
AVBufferRef
A reference to a data buffer.
Definition: buffer.h:82
src
INIT_CLIP pixel * src
Definition: h264pred_template.c:418
int
int
Definition: ffmpeg_filter.c:424
FFHWAccel::caps_internal
int caps_internal
Internal hwaccel capabilities.
Definition: hwaccel_internal.h:117
FFHWAccel::update_thread_context
int(* update_thread_context)(AVCodecContext *dst, const AVCodecContext *src)
Copy necessary context variables from a previous thread context to the current one.
Definition: hwaccel_internal.h:150