FFmpeg
idctdsp.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 #ifndef AVCODEC_IDCTDSP_H
20 #define AVCODEC_IDCTDSP_H
21 
22 #include <stdint.h>
23 
24 #include "config.h"
25 
26 #include "avcodec.h"
27 
28 /**
29  * Scantable.
30  */
31 typedef struct ScanTable {
35 } ScanTable;
36 
44 };
45 
46 void ff_init_scantable(uint8_t *permutation, ScanTable *st,
47  const uint8_t *src_scantable);
48 void ff_init_scantable_permutation(uint8_t *idct_permutation,
49  enum idct_permutation_type perm_type);
50 int ff_init_scantable_permutation_x86(uint8_t *idct_permutation,
51  enum idct_permutation_type perm_type);
52 
53 typedef struct IDCTDSPContext {
54  /* pixel ops : interface with DCT */
55  void (*put_pixels_clamped)(const int16_t *block /* align 16 */,
56  uint8_t *av_restrict pixels /* align 8 */,
57  ptrdiff_t line_size);
58  void (*put_signed_pixels_clamped)(const int16_t *block /* align 16 */,
59  uint8_t *av_restrict pixels /* align 8 */,
60  ptrdiff_t line_size);
61  void (*add_pixels_clamped)(const int16_t *block /* align 16 */,
62  uint8_t *av_restrict pixels /* align 8 */,
63  ptrdiff_t line_size);
64 
65  void (*idct)(int16_t *block /* align 16 */);
66 
67  /**
68  * block -> idct -> clip to unsigned 8 bit -> dest.
69  * (-1392, 0, 0, ...) -> idct -> (-174, -174, ...) -> put -> (0, 0, ...)
70  * @param line_size size in bytes of a horizontal line of dest
71  */
72  void (*idct_put)(uint8_t *dest /* align 8 */,
73  ptrdiff_t line_size, int16_t *block /* align 16 */);
74 
75  /**
76  * block -> idct -> add dest -> clip to unsigned 8 bit -> dest.
77  * @param line_size size in bytes of a horizontal line of dest
78  */
79  void (*idct_add)(uint8_t *dest /* align 8 */,
80  ptrdiff_t line_size, int16_t *block /* align 16 */);
81 
82  /**
83  * IDCT input permutation.
84  * Several optimized IDCTs need a permutated input (relative to the
85  * normal order of the reference IDCT).
86  * This permutation must be performed before the idct_put/add.
87  * Note, normally this can be merged with the zigzag/alternate scan<br>
88  * An example to avoid confusion:
89  * - (->decode coeffs -> zigzag reorder -> dequant -> reference IDCT -> ...)
90  * - (x -> reference DCT -> reference IDCT -> x)
91  * - (x -> reference DCT -> simple_mmx_perm = idct_permutation
92  * -> simple_idct_mmx -> x)
93  * - (-> decode coeffs -> zigzag reorder -> simple_mmx_perm -> dequant
94  * -> simple_idct_mmx -> ...)
95  */
96  uint8_t idct_permutation[64];
97  enum idct_permutation_type perm_type;
98 
101 
102 void ff_put_pixels_clamped_c(const int16_t *block, uint8_t *av_restrict pixels,
103  ptrdiff_t line_size);
104 void ff_add_pixels_clamped_c(const int16_t *block, uint8_t *av_restrict pixels,
105  ptrdiff_t line_size);
106 
108 
110  unsigned high_bit_depth);
112  unsigned high_bit_depth);
114  unsigned high_bit_depth);
116  unsigned high_bit_depth);
118  unsigned high_bit_depth);
120  unsigned high_bit_depth);
121 
122 #endif /* AVCODEC_IDCTDSP_H */
void ff_idctdsp_init_x86(IDCTDSPContext *c, AVCodecContext *avctx, unsigned high_bit_depth)
Definition: idctdsp_init.c:61
int ff_init_scantable_permutation_x86(uint8_t *idct_permutation, enum idct_permutation_type perm_type)
Definition: idctdsp_init.c:42
idct_permutation_type
Definition: idctdsp.h:37
void ff_idctdsp_init(IDCTDSPContext *c, AVCodecContext *avctx)
Definition: idctdsp.c:238
void ff_add_pixels_clamped_c(const int16_t *block, uint8_t *av_restrict pixels, ptrdiff_t line_size)
Definition: idctdsp.c:157
static void idct(int16_t block[64])
Definition: 4xm.c:163
Scantable.
Definition: idctdsp.h:31
uint8_t raster_end[64]
Definition: idctdsp.h:34
uint8_t permutated[64]
Definition: idctdsp.h:33
void ff_idctdsp_init_arm(IDCTDSPContext *c, AVCodecContext *avctx, unsigned high_bit_depth)
The exact code depends on how similar the blocks are and how related they are to the block
uint8_t
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
const uint8_t * scantable
Definition: idctdsp.h:32
int mpeg4_studio_profile
Definition: idctdsp.h:99
void ff_init_scantable(uint8_t *permutation, ScanTable *st, const uint8_t *src_scantable)
Definition: idctdsp.c:29
void ff_idctdsp_init_mips(IDCTDSPContext *c, AVCodecContext *avctx, unsigned high_bit_depth)
typedef void(APIENTRY *FF_PFNGLACTIVETEXTUREPROC)(GLenum texture)
void ff_init_scantable_permutation(uint8_t *idct_permutation, enum idct_permutation_type perm_type)
Definition: idctdsp.c:50
void ff_idctdsp_init_aarch64(IDCTDSPContext *c, AVCodecContext *avctx, unsigned high_bit_depth)
static void idct_put(FourXContext *f, int x, int y)
Definition: 4xm.c:556
void ff_idctdsp_init_alpha(IDCTDSPContext *c, AVCodecContext *avctx, unsigned high_bit_depth)
Libavcodec external API header.
void ff_idctdsp_init_ppc(IDCTDSPContext *c, AVCodecContext *avctx, unsigned high_bit_depth)
Definition: idctdsp.c:255
main external API structure.
Definition: avcodec.h:1570
int pixels
Definition: avisynth_c.h:390
void ff_put_pixels_clamped_c(const int16_t *block, uint8_t *av_restrict pixels, ptrdiff_t line_size)
Definition: idctdsp.c:83