Implement YOP demuxer and video decoder.
Patch by Mohamed Naufal gmailify(naufal11). Originally committed as revision 22724 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Mohamed Naufal
Stefano Sabatini
parent
30ad1a6651
commit
148bcae98c
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@ -241,6 +241,7 @@ library:
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@item Westwood Studios VQA @tab @tab X
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@tab Multimedia format used in Westwood Studios games.
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@item YUV4MPEG pipe @tab X @tab X
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@item Psygnosis YOP @tab @tab X
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@end multitable
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@code{X} means that encoding (resp. decoding) is supported.
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@ -490,6 +491,7 @@ following image formats are supported:
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@item Winnov WNV1 @tab @tab X
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@item WMV7 @tab X @tab X
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@item YAMAHA SMAF @tab X @tab X
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@item Psygnosis YOP Video @tab @tab X
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@item ZLIB @tab X @tab X
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@tab part of LCL, encoder experimental
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@item Zip Motion Blocks Video @tab X @tab X
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@ -386,6 +386,7 @@ OBJS-$(CONFIG_XAN_WC4_DECODER) += xan.o
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OBJS-$(CONFIG_XL_DECODER) += xl.o
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OBJS-$(CONFIG_XSUB_DECODER) += xsubdec.o
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OBJS-$(CONFIG_XSUB_ENCODER) += xsubenc.o
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OBJS-$(CONFIG_YOP_DECODER) += yop.o
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OBJS-$(CONFIG_ZLIB_DECODER) += lcldec.o
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OBJS-$(CONFIG_ZLIB_ENCODER) += lclenc.o
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OBJS-$(CONFIG_ZMBV_DECODER) += zmbv.o
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@ -207,6 +207,7 @@ void avcodec_register_all(void)
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REGISTER_DECODER (WNV1, wnv1);
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REGISTER_DECODER (XAN_WC3, xan_wc3);
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REGISTER_DECODER (XL, xl);
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REGISTER_DECODER (YOP, yop);
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REGISTER_ENCDEC (ZLIB, zlib);
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REGISTER_ENCDEC (ZMBV, zmbv);
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@ -30,7 +30,7 @@
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#include "libavutil/avutil.h"
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#define LIBAVCODEC_VERSION_MAJOR 52
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#define LIBAVCODEC_VERSION_MINOR 61
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#define LIBAVCODEC_VERSION_MINOR 62
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#define LIBAVCODEC_VERSION_MICRO 0
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#define LIBAVCODEC_VERSION_INT AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
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@ -209,6 +209,7 @@ enum CodecID {
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CODEC_ID_IFF_ILBM,
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CODEC_ID_IFF_BYTERUN1,
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CODEC_ID_KGV1,
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CODEC_ID_YOP,
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/* various PCM "codecs" */
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CODEC_ID_PCM_S16LE= 0x10000,
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260
libavcodec/yop.c
Normal file
260
libavcodec/yop.c
Normal file
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@ -0,0 +1,260 @@
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/**
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* @file libavcodec/yop.c
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* Psygnosis YOP decoder
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*
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* Copyright (C) 2010 Mohamed Naufal Basheer <naufal11@gmail.com>
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* derived from the code by
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* Copyright (C) 2009 Thomas P. Higdon <thomas.p.higdon@gmail.com>
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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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#include "libavutil/intreadwrite.h"
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#include "avcodec.h"
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#include "get_bits.h"
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typedef struct YopDecContext {
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AVFrame frame;
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AVCodecContext *avctx;
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int num_pal_colors;
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int first_color[2];
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int frame_data_length;
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int row_pos;
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uint8_t *low_nibble;
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uint8_t *srcptr;
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uint8_t *dstptr;
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uint8_t *dstbuf;
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} YopDecContext;
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// These tables are taken directly from:
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// http://wiki.multimedia.cx/index.php?title=Psygnosis_YOP
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/**
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* Lookup table for painting macroblocks. Bytes 0-2 of each entry contain
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* the macroblock positions to be painted (taken as (0, B0, B1, B2)).
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* Byte 3 contains the number of bytes consumed on the input,
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* equal to max(bytes 0-2) + 1.
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*/
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static const uint8_t paint_lut[15][4] =
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{{1, 2, 3, 4}, {1, 2, 0, 3},
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{1, 2, 1, 3}, {1, 2, 2, 3},
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{1, 0, 2, 3}, {1, 0, 0, 2},
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{1, 0, 1, 2}, {1, 1, 2, 3},
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{0, 1, 2, 3}, {0, 1, 0, 2},
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{1, 1, 0, 2}, {0, 1, 1, 2},
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{0, 0, 1, 2}, {0, 0, 0, 1},
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{1, 1, 1, 2},
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};
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/**
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* Lookup table for copying macroblocks. Each entry contains the respective
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* x and y pixel offset for the copy source.
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*/
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static const int8_t motion_vector[16][2] =
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{{-4, -4}, {-2, -4},
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{ 0, -4}, { 2, -4},
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{-4, -2}, {-4, 0},
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{-3, -3}, {-1, -3},
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{ 1, -3}, { 3, -3},
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{-3, -1}, {-2, -2},
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{ 0, -2}, { 2, -2},
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{ 4, -2}, {-2, 0},
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};
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static av_cold int yop_decode_init(AVCodecContext *avctx)
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{
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YopDecContext *s = avctx->priv_data;
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s->avctx = avctx;
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if (avctx->width & 1 || avctx->height & 1 ||
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avcodec_check_dimensions(avctx, avctx->width, avctx->height) < 0) {
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av_log(avctx, AV_LOG_ERROR, "YOP has invalid dimensions\n");
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return -1;
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}
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avctx->pix_fmt = PIX_FMT_PAL8;
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s->num_pal_colors = avctx->extradata[0];
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s->first_color[0] = avctx->extradata[1];
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s->first_color[1] = avctx->extradata[2];
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if (s->num_pal_colors + s->first_color[0] > 256 ||
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s->num_pal_colors + s->first_color[1] > 256) {
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av_log(avctx, AV_LOG_ERROR,
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"YOP: palette parameters invalid, header probably corrupt\n");
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return AVERROR_INVALIDDATA;
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}
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return 0;
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}
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static av_cold int yop_decode_close(AVCodecContext *avctx)
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{
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YopDecContext *s = avctx->priv_data;
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if (s->frame.data[0])
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avctx->release_buffer(avctx, &s->frame);
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return 0;
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}
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/**
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* Paints a macroblock using the pattern in paint_lut.
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* @param s codec context
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* @param tag the tag that was in the nibble
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*/
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static void yop_paint_block(YopDecContext *s, int tag)
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{
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s->dstptr[0] = s->srcptr[0];
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s->dstptr[1] = s->srcptr[paint_lut[tag][0]];
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s->dstptr[s->frame.linesize[0]] = s->srcptr[paint_lut[tag][1]];
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s->dstptr[s->frame.linesize[0] + 1] = s->srcptr[paint_lut[tag][2]];
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// The number of src bytes consumed is in the last part of the lut entry.
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s->srcptr += paint_lut[tag][3];
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}
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/**
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* Copies a previously painted macroblock to the current_block.
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* @param copy_tag the tag that was in the nibble
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*/
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static int yop_copy_previous_block(YopDecContext *s, int copy_tag)
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{
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uint8_t *bufptr;
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// Calculate position for the copy source
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bufptr = s->dstptr + motion_vector[copy_tag][0] +
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s->frame.linesize[0] * motion_vector[copy_tag][1];
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if (bufptr < s->dstbuf) {
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av_log(s->avctx, AV_LOG_ERROR,
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"YOP: cannot decode, file probably corrupt\n");
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return AVERROR_INVALIDDATA;
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}
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s->dstptr[0] = bufptr[0];
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s->dstptr[1] = bufptr[1];
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s->dstptr[s->frame.linesize[0]] = bufptr[s->frame.linesize[0]];
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s->dstptr[s->frame.linesize[0] + 1] = bufptr[s->frame.linesize[0] + 1];
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return 0;
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}
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/**
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* Returns the next nibble in sequence, consuming a new byte on the input
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* only if necessary.
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*/
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static uint8_t yop_get_next_nibble(YopDecContext *s)
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{
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int ret;
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if (s->low_nibble) {
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ret = *s->low_nibble & 0xf;
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s->low_nibble = NULL;
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}else {
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s->low_nibble = s->srcptr++;
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ret = *s->low_nibble >> 4;
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}
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return ret;
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}
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/**
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* Takes s->dstptr to the next macroblock in sequence.
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*/
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static void yop_next_macroblock(YopDecContext *s)
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{
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// If we are advancing to the next row of macroblocks
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if (s->row_pos == s->frame.linesize[0] - 2) {
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s->dstptr += s->frame.linesize[0];
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s->row_pos = 0;
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}else {
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s->row_pos += 2;
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}
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s->dstptr += 2;
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}
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static int yop_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
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AVPacket *avpkt)
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{
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YopDecContext *s = avctx->priv_data;
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int tag, firstcolor, is_odd_frame;
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int ret, i;
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uint32_t *palette;
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if (s->frame.data[0])
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avctx->release_buffer(avctx, &s->frame);
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ret = avctx->get_buffer(avctx, &s->frame);
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if (ret < 0) {
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av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
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return ret;
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}
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s->frame.linesize[0] = avctx->width;
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s->dstbuf = s->frame.data[0];
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s->dstptr = s->frame.data[0];
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s->srcptr = avpkt->data + 4;
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s->row_pos = 0;
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s->low_nibble = NULL;
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is_odd_frame = avpkt->data[0];
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firstcolor = s->first_color[is_odd_frame];
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palette = (uint32_t *)s->frame.data[1];
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for (i = 0; i < s->num_pal_colors; i++, s->srcptr += 3)
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palette[i + firstcolor] = (s->srcptr[0] << 18) |
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(s->srcptr[1] << 10) |
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(s->srcptr[2] << 2);
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s->frame.palette_has_changed = 1;
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while (s->dstptr - s->dstbuf <
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avctx->width * avctx->height &&
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s->srcptr - avpkt->data < avpkt->size) {
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tag = yop_get_next_nibble(s);
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if (tag != 0xf) {
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yop_paint_block(s, tag);
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}else {
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tag = yop_get_next_nibble(s);
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ret = yop_copy_previous_block(s, tag);
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if (ret < 0) {
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avctx->release_buffer(avctx, &s->frame);
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return ret;
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}
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}
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yop_next_macroblock(s);
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}
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*data_size = sizeof(AVFrame);
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*(AVFrame *) data = s->frame;
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return avpkt->size;
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}
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AVCodec yop_decoder = {
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"yop",
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CODEC_TYPE_VIDEO,
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CODEC_ID_YOP,
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sizeof(YopDecContext),
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yop_decode_init,
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NULL,
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yop_decode_close,
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yop_decode_frame,
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.long_name = NULL_IF_CONFIG_SMALL("Psygnosis YOP Video"),
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};
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@ -260,6 +260,7 @@ OBJS-$(CONFIG_WSAUD_DEMUXER) += westwood.o
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OBJS-$(CONFIG_WSVQA_DEMUXER) += westwood.o
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OBJS-$(CONFIG_WV_DEMUXER) += wv.o apetag.o id3v1.o
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OBJS-$(CONFIG_XA_DEMUXER) += xa.o
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OBJS-$(CONFIG_YOP_DEMUXER) += yop.o
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OBJS-$(CONFIG_YUV4MPEGPIPE_MUXER) += yuv4mpeg.o
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OBJS-$(CONFIG_YUV4MPEGPIPE_DEMUXER) += yuv4mpeg.o
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@ -207,6 +207,7 @@ void av_register_all(void)
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REGISTER_DEMUXER (WSVQA, wsvqa);
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REGISTER_DEMUXER (WV, wv);
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REGISTER_DEMUXER (XA, xa);
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REGISTER_DEMUXER (YOP, yop);
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REGISTER_MUXDEMUX (YUV4MPEGPIPE, yuv4mpegpipe);
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/* external libraries */
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@ -22,7 +22,7 @@
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#define AVFORMAT_AVFORMAT_H
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#define LIBAVFORMAT_VERSION_MAJOR 52
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#define LIBAVFORMAT_VERSION_MINOR 58
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#define LIBAVFORMAT_VERSION_MINOR 59
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#define LIBAVFORMAT_VERSION_MICRO 0
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#define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \
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216
libavformat/yop.c
Normal file
216
libavformat/yop.c
Normal file
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@ -0,0 +1,216 @@
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/**
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* @file libavformat/yop.c
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* Psygnosis YOP demuxer
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*
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* Copyright (C) 2010 Mohamed Naufal Basheer <naufal11@gmail.com>
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* derived from the code by
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* Copyright (C) 2009 Thomas P. Higdon <thomas.p.higdon@gmail.com>
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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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#include "libavutil/intreadwrite.h"
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#include "avformat.h"
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typedef struct yop_dec_context {
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AVPacket video_packet;
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int odd_frame;
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int frame_size;
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int audio_block_length;
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int palette_size;
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} YopDecContext;
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static int yop_probe(AVProbeData *probe_packet)
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{
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if (AV_RB16(probe_packet->buf) == AV_RB16("YO") &&
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probe_packet->buf[6] &&
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probe_packet->buf[7] &&
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!(probe_packet->buf[8] & 1) &&
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!(probe_packet->buf[10] & 1))
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return AVPROBE_SCORE_MAX * 3 / 4;
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return 0;
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}
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static int yop_read_header(AVFormatContext *s, AVFormatParameters *ap)
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{
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YopDecContext *yop = s->priv_data;
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ByteIOContext *pb = s->pb;
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AVCodecContext *audio_dec, *video_dec;
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AVStream *audio_stream, *video_stream;
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int frame_rate, ret;
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audio_stream = av_new_stream(s, 0);
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video_stream = av_new_stream(s, 1);
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// Extra data that will be passed to the decoder
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video_stream->codec->extradata_size = 8;
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video_stream->codec->extradata = av_mallocz(video_stream->codec->extradata_size +
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FF_INPUT_BUFFER_PADDING_SIZE);
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if (!video_stream->codec->extradata)
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return AVERROR(ENOMEM);
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// Audio
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audio_dec = audio_stream->codec;
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audio_dec->codec_type = CODEC_TYPE_AUDIO;
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audio_dec->codec_id = CODEC_ID_ADPCM_IMA_WS;
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audio_dec->channels = 1;
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audio_dec->sample_rate = 22050;
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// Video
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video_dec = video_stream->codec;
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video_dec->codec_type = CODEC_TYPE_VIDEO;
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video_dec->codec_id = CODEC_ID_YOP;
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url_fskip(pb, 6);
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frame_rate = get_byte(pb);
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yop->frame_size = get_byte(pb) * 2048;
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video_dec->width = get_le16(pb);
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video_dec->height = get_le16(pb);
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video_stream->sample_aspect_ratio = (AVRational){1, 2};
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|
||||
ret = get_buffer(pb, video_dec->extradata, 8);
|
||||
if (ret < 8)
|
||||
return ret < 0 ? ret : AVERROR_EOF;
|
||||
|
||||
yop->palette_size = video_dec->extradata[0] * 3 + 4;
|
||||
yop->audio_block_length = AV_RL16(video_dec->extradata + 6);
|
||||
|
||||
// 1840 samples per frame, 1 nibble per sample; hence 1840/2 = 920
|
||||
if (yop->audio_block_length < 920 ||
|
||||
yop->audio_block_length + yop->palette_size >= yop->frame_size) {
|
||||
av_log(s, AV_LOG_ERROR, "YOP has invalid header\n");
|
||||
return AVERROR_INVALIDDATA;
|
||||
}
|
||||
|
||||
url_fseek(pb, 2048, SEEK_SET);
|
||||
|
||||
av_set_pts_info(video_stream, 32, 1, frame_rate);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int yop_read_packet(AVFormatContext *s, AVPacket *pkt)
|
||||
{
|
||||
YopDecContext *yop = s->priv_data;
|
||||
ByteIOContext *pb = s->pb;
|
||||
|
||||
int ret;
|
||||
int actual_video_data_size = yop->frame_size -
|
||||
yop->audio_block_length - yop->palette_size;
|
||||
|
||||
yop->video_packet.stream_index = 1;
|
||||
|
||||
if (yop->video_packet.data) {
|
||||
*pkt = yop->video_packet;
|
||||
yop->video_packet.data = NULL;
|
||||
yop->video_packet.size = 0;
|
||||
pkt->data[0] = yop->odd_frame;
|
||||
pkt->flags |= PKT_FLAG_KEY;
|
||||
yop->odd_frame ^= 1;
|
||||
return pkt->size;
|
||||
}
|
||||
ret = av_new_packet(&yop->video_packet,
|
||||
yop->frame_size - yop->audio_block_length);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
|
||||
yop->video_packet.pos = url_ftell(pb);
|
||||
|
||||
ret = get_buffer(pb, yop->video_packet.data, yop->palette_size);
|
||||
if (ret < 0) {
|
||||
goto err_out;
|
||||
}else if (ret < yop->palette_size) {
|
||||
ret = AVERROR_EOF;
|
||||
goto err_out;
|
||||
}
|
||||
|
||||
ret = av_get_packet(pb, pkt, 920);
|
||||
if (ret < 0)
|
||||
goto err_out;
|
||||
|
||||
// Set position to the start of the frame
|
||||
pkt->pos = yop->video_packet.pos;
|
||||
|
||||
url_fskip(pb, yop->audio_block_length - ret);
|
||||
|
||||
ret = get_buffer(pb, yop->video_packet.data + yop->palette_size,
|
||||
actual_video_data_size);
|
||||
if (ret < 0)
|
||||
goto err_out;
|
||||
else if (ret < actual_video_data_size)
|
||||
av_shrink_packet(&yop->video_packet, yop->palette_size + ret);
|
||||
|
||||
// Arbitrarily return the audio data first
|
||||
return yop->audio_block_length;
|
||||
|
||||
err_out:
|
||||
av_free_packet(&yop->video_packet);
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int yop_read_close(AVFormatContext *s)
|
||||
{
|
||||
YopDecContext *yop = s->priv_data;
|
||||
av_free_packet(&yop->video_packet);
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int yop_read_seek(AVFormatContext *s, int stream_index,
|
||||
int64_t timestamp, int flags)
|
||||
{
|
||||
YopDecContext *yop = s->priv_data;
|
||||
int64_t frame_pos, pos_min, pos_max;
|
||||
int frame_count;
|
||||
|
||||
av_free_packet(&yop->video_packet);
|
||||
|
||||
if (!stream_index)
|
||||
return -1;
|
||||
|
||||
pos_min = s->data_offset;
|
||||
pos_max = url_fsize(s->pb) - yop->frame_size;
|
||||
frame_count = (pos_max - pos_min) / yop->frame_size;
|
||||
|
||||
timestamp = FFMAX(0, FFMIN(frame_count, timestamp));
|
||||
|
||||
frame_pos = timestamp * yop->frame_size + pos_min;
|
||||
yop->odd_frame = timestamp & 1;
|
||||
|
||||
url_fseek(s->pb, frame_pos, SEEK_SET);
|
||||
return 0;
|
||||
}
|
||||
|
||||
AVInputFormat yop_demuxer = {
|
||||
"yop",
|
||||
NULL_IF_CONFIG_SMALL("Psygnosis YOP Format"),
|
||||
sizeof(YopDecContext),
|
||||
yop_probe,
|
||||
yop_read_header,
|
||||
yop_read_packet,
|
||||
yop_read_close,
|
||||
yop_read_seek,
|
||||
.extensions = "yop",
|
||||
.flags = AVFMT_GENERIC_INDEX,
|
||||
};
|
||||
Loading…
Reference in New Issue
Block a user