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111 lines
4.1 KiB
C
111 lines
4.1 KiB
C
/*
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* MJPEG encoder
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* Copyright (c) 2000, 2001 Fabrice Bellard
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* Copyright (c) 2003 Alex Beregszaszi
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* Copyright (c) 2003-2004 Michael Niedermayer
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*
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* Support for external huffman table, various fixes (AVID workaround),
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* aspecting, new decode_frame mechanism and apple mjpeg-b support
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* by Alex Beregszaszi
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*
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* This file is part of FFmpeg.
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*
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* FFmpeg is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* FFmpeg is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with FFmpeg; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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/**
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* @file
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* MJPEG encoder.
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*/
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#ifndef AVCODEC_MJPEGENC_H
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#define AVCODEC_MJPEGENC_H
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#include <stdint.h>
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#include "mjpeg.h"
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#include "mpegvideo.h"
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#include "put_bits.h"
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/**
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* Buffer of JPEG frame data.
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*
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* Optimal Huffman table generation requires the frame data to be loaded into
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* a buffer so that the tables can be computed.
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* There are at most mb_width*mb_height*12*64 of these per frame.
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*/
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typedef struct MJpegHuffmanCode {
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// 0=DC lum, 1=DC chrom, 2=AC lum, 3=AC chrom
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uint8_t table_id; ///< The Huffman table id associated with the data.
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uint8_t code; ///< The exponent.
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uint16_t mant; ///< The mantissa.
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} MJpegHuffmanCode;
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/**
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* Holds JPEG frame data and Huffman table data.
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*/
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typedef struct MJpegContext {
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//FIXME use array [3] instead of lumi / chroma, for easier addressing
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uint8_t huff_size_dc_luminance[12]; ///< DC luminance Huffman table size.
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uint16_t huff_code_dc_luminance[12]; ///< DC luminance Huffman table codes.
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uint8_t huff_size_dc_chrominance[12]; ///< DC chrominance Huffman table size.
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uint16_t huff_code_dc_chrominance[12]; ///< DC chrominance Huffman table codes.
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uint8_t huff_size_ac_luminance[256]; ///< AC luminance Huffman table size.
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uint16_t huff_code_ac_luminance[256]; ///< AC luminance Huffman table codes.
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uint8_t huff_size_ac_chrominance[256]; ///< AC chrominance Huffman table size.
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uint16_t huff_code_ac_chrominance[256]; ///< AC chrominance Huffman table codes.
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/** Storage for AC luminance VLC (in MpegEncContext) */
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uint8_t uni_ac_vlc_len[64 * 64 * 2];
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/** Storage for AC chrominance VLC (in MpegEncContext) */
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uint8_t uni_chroma_ac_vlc_len[64 * 64 * 2];
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// Default DC tables have exactly 12 values
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uint8_t bits_dc_luminance[17]; ///< DC luminance Huffman bits.
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uint8_t val_dc_luminance[12]; ///< DC luminance Huffman values.
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uint8_t bits_dc_chrominance[17]; ///< DC chrominance Huffman bits.
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uint8_t val_dc_chrominance[12]; ///< DC chrominance Huffman values.
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// 8-bit JPEG has max 256 values
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uint8_t bits_ac_luminance[17]; ///< AC luminance Huffman bits.
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uint8_t val_ac_luminance[256]; ///< AC luminance Huffman values.
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uint8_t bits_ac_chrominance[17]; ///< AC chrominance Huffman bits.
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uint8_t val_ac_chrominance[256]; ///< AC chrominance Huffman values.
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size_t huff_ncode; ///< Number of current entries in the buffer.
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MJpegHuffmanCode *huff_buffer; ///< Buffer for Huffman code values.
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} MJpegContext;
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/**
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* Enum for the Huffman encoding strategy.
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*/
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enum HuffmanTableOption {
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HUFFMAN_TABLE_DEFAULT = 0, ///< Use the default Huffman tables.
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HUFFMAN_TABLE_OPTIMAL = 1, ///< Compute and use optimal Huffman tables.
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NB_HUFFMAN_TABLE_OPTION = 2
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};
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static inline void put_marker(PutBitContext *p, enum JpegMarker code)
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{
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put_bits(p, 8, 0xff);
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put_bits(p, 8, code);
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}
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int ff_mjpeg_encode_init(MpegEncContext *s);
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void ff_mjpeg_encode_close(MpegEncContext *s);
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void ff_mjpeg_encode_mb(MpegEncContext *s, int16_t block[12][64]);
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#endif /* AVCODEC_MJPEGENC_H */
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