1 /*
2  *  Copyright (c) 2014 The WebM project authors. All Rights Reserved.
3  *
4  *  Use of this source code is governed by a BSD-style license
5  *  that can be found in the LICENSE file in the root of the source
6  *  tree. An additional intellectual property rights grant can be found
7  *  in the file PATENTS.  All contributing project authors may
8  *  be found in the AUTHORS file in the root of the source tree.
9  */
10 
11 #ifndef VPX_VPX_FRAME_BUFFER_H_
12 #define VPX_VPX_FRAME_BUFFER_H_
13 
14 /*!\file
15  * \brief Describes the decoder external frame buffer interface.
16  */
17 
18 #ifdef __cplusplus
19 extern "C" {
20 #endif
21 
22 #include "./vpx_integer.h"
23 
24 /*!\brief The maximum number of work buffers used by libvpx.
25  */
26 #define VPX_MAXIMUM_WORK_BUFFERS 1
27 
28 /*!\brief The maximum number of reference buffers that a VP9 encoder may use.
29  */
30 #define VP9_MAXIMUM_REF_BUFFERS 8
31 
32 /*!\brief External frame buffer
33  *
34  * This structure holds allocated frame buffers used by the decoder.
35  */
36 typedef struct vpx_codec_frame_buffer {
37   uint8_t *data;  /**< Pointer to the data buffer */
38   size_t size;  /**< Size of data in bytes */
39   void *priv;  /**< Frame's private data */
40 
41   int fb_index;
42   int fb_stride;
43   int fb_height_stride;
44 } vpx_codec_frame_buffer_t;
45 
46 /*!\brief get frame buffer callback prototype
47  *
48  * This callback is invoked by the decoder to retrieve data for the frame
49  * buffer in order for the decode call to complete. The callback must
50  * allocate at least min_size in bytes and assign it to fb->data. Then the
51  * callback must set fb->size to the allocated size. The application does not
52  * need to align the allocated data. The callback is triggered when the
53  * decoder needs a frame buffer to decode a compressed image into. This
54  * function may be called more than once for every call to vpx_codec_decode.
55  * The application may set fb->priv to some data which will be passed
56  * back in the ximage and the release function call. |fb| is guaranteed to
57  * not be NULL. On success the callback must return 0. Any failure the
58  * callback must return a value less than 0.
59  *
60  * \param[in] priv         Callback's private data
61  * \param[in] new_size     Size in bytes needed by the buffer
62  * \param[in,out] fb       Pointer to vpx_codec_frame_buffer_t
63  */
64 typedef int (*vpx_get_frame_buffer_cb_fn_t)(
65     void *priv, size_t min_size, vpx_codec_frame_buffer_t *fb);
66 
67 /*!\brief release frame buffer callback prototype
68  *
69  * This callback is invoked by the decoder when the frame buffer is not
70  * referenced by any other buffers. |fb| is guaranteed to not be NULL. On
71  * success the callback must return 0. Any failure the callback must return
72  * a value less than 0.
73  *
74  * \param[in] priv         Callback's private data
75  * \param[in] fb           Pointer to vpx_codec_frame_buffer_t
76  */
77 typedef int (*vpx_release_frame_buffer_cb_fn_t)(
78     void *priv, vpx_codec_frame_buffer_t *fb);
79 
80 #ifdef __cplusplus
81 }  // extern "C"
82 #endif
83 
84 #endif  // VPX_VPX_FRAME_BUFFER_H_
85