1 /*
2  *  Copyright (c) 2010 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 /*!\defgroup vp8 VP8
12  * \ingroup codecs
13  * VP8 is a video compression algorithm that uses motion
14  * compensated prediction, Discrete Cosine Transform (DCT) coding of the
15  * prediction error signal and context dependent entropy coding techniques
16  * based on arithmetic principles. It features:
17  *  - YUV 4:2:0 image format
18  *  - Macro-block based coding (16x16 luma plus two 8x8 chroma)
19  *  - 1/4 (1/8) pixel accuracy motion compensated prediction
20  *  - 4x4 DCT transform
21  *  - 128 level linear quantizer
22  *  - In loop deblocking filter
23  *  - Context-based entropy coding
24  *
25  * @{
26  */
27 /*!\file
28  * \brief Provides controls common to both the VP8 encoder and decoder.
29  */
30 #ifndef VPX_VPX_VP8_H_
31 #define VPX_VPX_VP8_H_
32 
33 #include "./vpx_codec.h"
34 #include "./vpx_image.h"
35 
36 #ifdef __cplusplus
37 extern "C" {
38 #endif
39 
40 /*!\brief Control functions
41  *
42  * The set of macros define the control functions of VP8 interface
43  */
44 enum vp8_com_control_id {
45   /*!\brief pass in an external frame into decoder to be used as reference frame
46    */
47   VP8_SET_REFERENCE = 1,
48   VP8_COPY_REFERENCE = 2, /**< get a copy of reference frame from the decoder */
49   VP8_SET_POSTPROC = 3,   /**< set the decoder's post processing settings  */
50 
51   /* TODO(jkoleszar): The encoder incorrectly reuses some of these values (5+)
52    * for its control ids. These should be migrated to something like the
53    * VP8_DECODER_CTRL_ID_START range next time we're ready to break the ABI.
54    */
55   VP9_GET_REFERENCE = 128, /**< get a pointer to a reference frame */
56   VP8_COMMON_CTRL_ID_MAX,
57   VP8_DECODER_CTRL_ID_START = 256
58 };
59 
60 /*!\brief post process flags
61  *
62  * The set of macros define VP8 decoder post processing flags
63  */
64 enum vp8_postproc_level {
65   VP8_NOFILTERING = 0,
66   VP8_DEBLOCK = 1 << 0,
67   VP8_DEMACROBLOCK = 1 << 1,
68   VP8_ADDNOISE = 1 << 2,
69   VP8_MFQE = 1 << 3
70 };
71 
72 /*!\brief post process flags
73  *
74  * This define a structure that describe the post processing settings. For
75  * the best objective measure (using the PSNR metric) set post_proc_flag
76  * to VP8_DEBLOCK and deblocking_level to 1.
77  */
78 
79 typedef struct vp8_postproc_cfg {
80   /*!\brief the types of post processing to be done, should be combination of
81    * "vp8_postproc_level" */
82   int post_proc_flag;
83   int deblocking_level; /**< the strength of deblocking, valid range [0, 16] */
84   int noise_level; /**< the strength of additive noise, valid range [0, 16] */
85 } vp8_postproc_cfg_t;
86 
87 /*!\brief reference frame type
88  *
89  * The set of macros define the type of VP8 reference frames
90  */
91 typedef enum vpx_ref_frame_type {
92   VP8_LAST_FRAME = 1,
93   VP8_GOLD_FRAME = 2,
94   VP8_ALTR_FRAME = 4
95 } vpx_ref_frame_type_t;
96 
97 /*!\brief reference frame data struct
98  *
99  * Define the data struct to access vp8 reference frames.
100  */
101 typedef struct vpx_ref_frame {
102   vpx_ref_frame_type_t frame_type; /**< which reference frame */
103   vpx_image_t img;                 /**< reference frame data in image format */
104 } vpx_ref_frame_t;
105 
106 /*!\brief VP9 specific reference frame data struct
107  *
108  * Define the data struct to access vp9 reference frames.
109  */
110 typedef struct vp9_ref_frame {
111   int idx;         /**< frame index to get (input) */
112   vpx_image_t img; /**< img structure to populate (output) */
113 } vp9_ref_frame_t;
114 
115 /*!\cond */
116 /*!\brief vp8 decoder control function parameter type
117  *
118  * defines the data type for each of VP8 decoder control function requires
119  */
120 VPX_CTRL_USE_TYPE(VP8_SET_REFERENCE, vpx_ref_frame_t *)
121 #define VPX_CTRL_VP8_SET_REFERENCE
122 VPX_CTRL_USE_TYPE(VP8_COPY_REFERENCE, vpx_ref_frame_t *)
123 #define VPX_CTRL_VP8_COPY_REFERENCE
124 VPX_CTRL_USE_TYPE(VP8_SET_POSTPROC, vp8_postproc_cfg_t *)
125 #define VPX_CTRL_VP8_SET_POSTPROC
126 VPX_CTRL_USE_TYPE(VP9_GET_REFERENCE, vp9_ref_frame_t *)
127 #define VPX_CTRL_VP9_GET_REFERENCE
128 
129 /*!\endcond */
130 /*! @} - end defgroup vp8 */
131 
132 #ifdef __cplusplus
133 }  // extern "C"
134 #endif
135 
136 #endif  // VPX_VPX_VP8_H_
137