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93 lines
2.4 KiB
C
93 lines
2.4 KiB
C
/*
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* VC-1 and WMV3 decoder
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* Copyright (c) 2006-2007 Konstantin Shishkov
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* Partly based on vc9.c (c) 2005 Anonymous, Alex Beregszaszi, Michael Niedermayer
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*
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* This file is part of Libav.
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*
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* Libav 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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* Libav 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 Libav; 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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#ifndef AVCODEC_VC1_COMMON_H
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#define AVCODEC_VC1_COMMON_H
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#include <stdint.h>
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#include "libavutil/attributes.h"
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/** Markers used in VC-1 AP frame data */
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//@{
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enum VC1Code {
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VC1_CODE_RES0 = 0x00000100,
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VC1_CODE_ENDOFSEQ = 0x0000010A,
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VC1_CODE_SLICE,
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VC1_CODE_FIELD,
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VC1_CODE_FRAME,
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VC1_CODE_ENTRYPOINT,
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VC1_CODE_SEQHDR,
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};
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//@}
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#define IS_MARKER(x) (((x) & ~0xFF) == VC1_CODE_RES0)
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/** Available Profiles */
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//@{
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enum Profile {
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PROFILE_SIMPLE,
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PROFILE_MAIN,
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PROFILE_COMPLEX, ///< TODO: WMV9 specific
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PROFILE_ADVANCED
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};
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//@}
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/** Find VC-1 marker in buffer
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* @return position where next marker starts or end of buffer if no marker found
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*/
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static av_always_inline const uint8_t* find_next_marker(const uint8_t *src, const uint8_t *end)
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{
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uint32_t mrk = 0xFFFFFFFF;
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if (end-src < 4)
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return end;
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while (src < end) {
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mrk = (mrk << 8) | *src++;
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if (IS_MARKER(mrk))
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return src - 4;
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}
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return end;
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}
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static av_always_inline int vc1_unescape_buffer(const uint8_t *src, int size, uint8_t *dst)
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{
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int dsize = 0, i;
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if (size < 4) {
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for (dsize = 0; dsize < size; dsize++)
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*dst++ = *src++;
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return size;
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}
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for (i = 0; i < size; i++, src++) {
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if (src[0] == 3 && i >= 2 && !src[-1] && !src[-2] && i < size-1 && src[1] < 4) {
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dst[dsize++] = src[1];
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src++;
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i++;
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} else
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dst[dsize++] = *src;
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}
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return dsize;
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}
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#endif /* AVCODEC_VC1_COMMON_H */
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