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mjpegenc.h
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1 /*
2  * MJPEG encoder
3  * Copyright (c) 2000, 2001 Fabrice Bellard
4  * Copyright (c) 2003 Alex Beregszaszi
5  * Copyright (c) 2003-2004 Michael Niedermayer
6  *
7  * Support for external huffman table, various fixes (AVID workaround),
8  * aspecting, new decode_frame mechanism and apple mjpeg-b support
9  * by Alex Beregszaszi
10  *
11  * This file is part of FFmpeg.
12  *
13  * FFmpeg is free software; you can redistribute it and/or
14  * modify it under the terms of the GNU Lesser General Public
15  * License as published by the Free Software Foundation; either
16  * version 2.1 of the License, or (at your option) any later version.
17  *
18  * FFmpeg is distributed in the hope that it will be useful,
19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
21  * Lesser General Public License for more details.
22  *
23  * You should have received a copy of the GNU Lesser General Public
24  * License along with FFmpeg; if not, write to the Free Software
25  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
26  */
27 
28 /**
29  * @file
30  * MJPEG encoder.
31  */
32 
33 #ifndef AVCODEC_MJPEGENC_H
34 #define AVCODEC_MJPEGENC_H
35 
36 #include <stdint.h>
37 
38 #include "mjpeg.h"
39 #include "mpegvideo.h"
40 #include "put_bits.h"
41 
42 /**
43  * Buffer of JPEG frame data.
44  *
45  * Optimal Huffman table generation requires the frame data to be loaded into
46  * a buffer so that the tables can be computed.
47  * There are at most mb_width*mb_height*12*64 of these per frame.
48  */
49 typedef struct MJpegHuffmanCode {
50  // 0=DC lum, 1=DC chrom, 2=AC lum, 3=AC chrom
51  uint8_t table_id; ///< The Huffman table id associated with the data.
52  uint8_t code; ///< The exponent.
53  uint16_t mant; ///< The mantissa.
55 
56 /**
57  * Holds JPEG frame data and Huffman table data.
58  */
59 typedef struct MJpegContext {
60  //FIXME use array [3] instead of lumi / chroma, for easier addressing
61  uint8_t huff_size_dc_luminance[12]; ///< DC luminance Huffman table size.
62  uint16_t huff_code_dc_luminance[12]; ///< DC luminance Huffman table codes.
63  uint8_t huff_size_dc_chrominance[12]; ///< DC chrominance Huffman table size.
64  uint16_t huff_code_dc_chrominance[12]; ///< DC chrominance Huffman table codes.
65 
66  uint8_t huff_size_ac_luminance[256]; ///< AC luminance Huffman table size.
67  uint16_t huff_code_ac_luminance[256]; ///< AC luminance Huffman table codes.
68  uint8_t huff_size_ac_chrominance[256]; ///< AC chrominance Huffman table size.
69  uint16_t huff_code_ac_chrominance[256]; ///< AC chrominance Huffman table codes.
70 
71  /** Storage for AC luminance VLC (in MpegEncContext) */
72  uint8_t uni_ac_vlc_len[64 * 64 * 2];
73  /** Storage for AC chrominance VLC (in MpegEncContext) */
75 
76  // Default DC tables have exactly 12 values
77  uint8_t bits_dc_luminance[17]; ///< DC luminance Huffman bits.
78  uint8_t val_dc_luminance[12]; ///< DC luminance Huffman values.
79  uint8_t bits_dc_chrominance[17]; ///< DC chrominance Huffman bits.
80  uint8_t val_dc_chrominance[12]; ///< DC chrominance Huffman values.
81 
82  // 8-bit JPEG has max 256 values
83  uint8_t bits_ac_luminance[17]; ///< AC luminance Huffman bits.
84  uint8_t val_ac_luminance[256]; ///< AC luminance Huffman values.
85  uint8_t bits_ac_chrominance[17]; ///< AC chrominance Huffman bits.
86  uint8_t val_ac_chrominance[256]; ///< AC chrominance Huffman values.
87 
88  size_t huff_ncode; ///< Number of current entries in the buffer.
89  MJpegHuffmanCode *huff_buffer; ///< Buffer for Huffman code values.
90 } MJpegContext;
91 
92 /**
93  * Enum for the Huffman encoding strategy.
94  */
96  HUFFMAN_TABLE_DEFAULT = 0, ///< Use the default Huffman tables.
97  HUFFMAN_TABLE_OPTIMAL = 1, ///< Compute and use optimal Huffman tables.
99 };
100 
101 static inline void put_marker(PutBitContext *p, enum JpegMarker code)
102 {
103  put_bits(p, 8, 0xff);
104  put_bits(p, 8, code);
105 }
106 
109 void ff_mjpeg_encode_mb(MpegEncContext *s, int16_t block[12][64]);
110 
111 #endif /* AVCODEC_MJPEGENC_H */
void ff_mjpeg_encode_mb(MpegEncContext *s, int16_t block[12][64])
Definition: mjpegenc.c:283
const char * s
Definition: avisynth_c.h:768
Holds JPEG frame data and Huffman table data.
Definition: mjpegenc.h:59
static void put_bits(Jpeg2000EncoderContext *s, int val, int n)
put n times val bit
Definition: j2kenc.c:206
mpegvideo header.
MJPEG encoder and decoder.
uint16_t huff_code_dc_chrominance[12]
DC chrominance Huffman table codes.
Definition: mjpegenc.h:64
static int16_t block[64]
Definition: dct.c:115
uint16_t huff_code_ac_luminance[256]
AC luminance Huffman table codes.
Definition: mjpegenc.h:67
uint8_t
uint8_t val_ac_luminance[256]
AC luminance Huffman values.
Definition: mjpegenc.h:84
uint8_t val_dc_chrominance[12]
DC chrominance Huffman values.
Definition: mjpegenc.h:80
uint8_t uni_chroma_ac_vlc_len[64 *64 *2]
Storage for AC chrominance VLC (in MpegEncContext)
Definition: mjpegenc.h:74
uint8_t huff_size_dc_chrominance[12]
DC chrominance Huffman table size.
Definition: mjpegenc.h:63
Use the default Huffman tables.
Definition: mjpegenc.h:96
uint8_t table_id
The Huffman table id associated with the data.
Definition: mjpegenc.h:51
uint16_t huff_code_ac_chrominance[256]
AC chrominance Huffman table codes.
Definition: mjpegenc.h:69
uint8_t huff_size_ac_luminance[256]
AC luminance Huffman table size.
Definition: mjpegenc.h:66
uint16_t mant
The mantissa.
Definition: mjpegenc.h:53
uint8_t huff_size_ac_chrominance[256]
AC chrominance Huffman table size.
Definition: mjpegenc.h:68
uint8_t bits_dc_luminance[17]
DC luminance Huffman bits.
Definition: mjpegenc.h:77
static void put_marker(PutBitContext *p, enum JpegMarker code)
Definition: mjpegenc.h:101
uint8_t val_ac_chrominance[256]
AC chrominance Huffman values.
Definition: mjpegenc.h:86
void ff_mjpeg_encode_close(MpegEncContext *s)
Definition: mjpegenc.c:126
uint8_t uni_ac_vlc_len[64 *64 *2]
Storage for AC luminance VLC (in MpegEncContext)
Definition: mjpegenc.h:72
int ff_mjpeg_encode_init(MpegEncContext *s)
Definition: mjpegenc.c:71
Compute and use optimal Huffman tables.
Definition: mjpegenc.h:97
Buffer of JPEG frame data.
Definition: mjpegenc.h:49
HuffmanTableOption
Enum for the Huffman encoding strategy.
Definition: mjpegenc.h:95
uint8_t bits_ac_chrominance[17]
AC chrominance Huffman bits.
Definition: mjpegenc.h:85
uint8_t val_dc_luminance[12]
DC luminance Huffman values.
Definition: mjpegenc.h:78
MpegEncContext.
Definition: mpegvideo.h:78
uint16_t huff_code_dc_luminance[12]
DC luminance Huffman table codes.
Definition: mjpegenc.h:62
uint8_t bits_dc_chrominance[17]
DC chrominance Huffman bits.
Definition: mjpegenc.h:79
uint8_t huff_size_dc_luminance[12]
DC luminance Huffman table size.
Definition: mjpegenc.h:61
uint8_t bits_ac_luminance[17]
AC luminance Huffman bits.
Definition: mjpegenc.h:83
uint8_t code
The exponent.
Definition: mjpegenc.h:52
size_t huff_ncode
Number of current entries in the buffer.
Definition: mjpegenc.h:88
JpegMarker
Definition: mjpeg.h:37
MJpegHuffmanCode * huff_buffer
Buffer for Huffman code values.
Definition: mjpegenc.h:89
bitstream writer API