From 589f82202c19c71ba6f430964a0f4d5ba52180af Mon Sep 17 00:00:00 2001 From: Mike Melanson Date: Sun, 3 Apr 2005 05:02:08 +0000 Subject: Autodesk Animator Studio Codec (AASC) video decoder, courtesy of Konstantin Shishkov Originally committed as revision 4099 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavcodec/aasc.c | 174 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 174 insertions(+) create mode 100644 libavcodec/aasc.c (limited to 'libavcodec/aasc.c') diff --git a/libavcodec/aasc.c b/libavcodec/aasc.c new file mode 100644 index 0000000000..d2419e98ce --- /dev/null +++ b/libavcodec/aasc.c @@ -0,0 +1,174 @@ +/* + * Autodesc RLE Decoder + * Copyright (C) 2005 the ffmpeg project + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +/** + * @file aasc.c + * Autodesc RLE Video Decoder by Konstantin Shishkov + */ + +#include +#include +#include + +#include "common.h" +#include "avcodec.h" +#include "dsputil.h" + +typedef struct AascContext { + AVCodecContext *avctx; + AVFrame frame; +} AascContext; + +#define FETCH_NEXT_STREAM_BYTE() \ + if (stream_ptr >= buf_size) \ + { \ + av_log(s->avctx, AV_LOG_ERROR, " AASC: stream ptr just went out of bounds (fetch)\n"); \ + break; \ + } \ + stream_byte = buf[stream_ptr++]; + +static int aasc_decode_init(AVCodecContext *avctx) +{ + AascContext *s = (AascContext *)avctx->priv_data; + + s->avctx = avctx; + + avctx->pix_fmt = PIX_FMT_BGR24; + avctx->has_b_frames = 0; + s->frame.data[0] = NULL; + + return 0; +} + +static int aasc_decode_frame(AVCodecContext *avctx, + void *data, int *data_size, + uint8_t *buf, int buf_size) +{ + AascContext *s = (AascContext *)avctx->priv_data; + int stream_ptr = 4; + unsigned char rle_code; + unsigned char stream_byte; + int pixel_ptr = 0; + int row_dec, row_ptr; + int frame_size; + int i; + + s->frame.reference = 1; + s->frame.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE; + if (avctx->reget_buffer(avctx, &s->frame)) { + av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n"); + return -1; + } + + row_dec = s->frame.linesize[0]; + row_ptr = (s->avctx->height - 1) * row_dec; + frame_size = row_dec * s->avctx->height; + + while (row_ptr >= 0) { + FETCH_NEXT_STREAM_BYTE(); + rle_code = stream_byte; + if (rle_code == 0) { + /* fetch the next byte to see how to handle escape code */ + FETCH_NEXT_STREAM_BYTE(); + if (stream_byte == 0) { + /* line is done, goto the next one */ + row_ptr -= row_dec; + pixel_ptr = 0; + } else if (stream_byte == 1) { + /* decode is done */ + break; + } else if (stream_byte == 2) { + /* reposition frame decode coordinates */ + FETCH_NEXT_STREAM_BYTE(); + pixel_ptr += stream_byte; + FETCH_NEXT_STREAM_BYTE(); + row_ptr -= stream_byte * row_dec; + } else { + /* copy pixels from encoded stream */ + if ((pixel_ptr + stream_byte > avctx->width * 3) || + (row_ptr < 0)) { + av_log(s->avctx, AV_LOG_ERROR, " AASC: frame ptr just went out of bounds (copy1)\n"); + break; + } + + rle_code = stream_byte; + if (stream_ptr + rle_code > buf_size) { + av_log(s->avctx, AV_LOG_ERROR, " AASC: stream ptr just went out of bounds (copy2)\n"); + break; + } + + for (i = 0; i < rle_code; i++) { + FETCH_NEXT_STREAM_BYTE(); + s->frame.data[0][row_ptr + pixel_ptr] = stream_byte; + pixel_ptr++; + } + if (rle_code & 1) + stream_ptr++; + } + } else { + /* decode a run of data */ + if ((pixel_ptr + rle_code > avctx->width * 3) || + (row_ptr < 0)) { + av_log(s->avctx, AV_LOG_ERROR, " AASC: frame ptr just went out of bounds (run1)\n"); + break; + } + + FETCH_NEXT_STREAM_BYTE(); + + while(rle_code--) { + s->frame.data[0][row_ptr + pixel_ptr] = stream_byte; + pixel_ptr++; + } + } + } + + /* one last sanity check on the way out */ + if (stream_ptr < buf_size) + av_log(s->avctx, AV_LOG_ERROR, " AASC: ended frame decode with bytes left over (%d < %d)\n", + stream_ptr, buf_size); + + *data_size = sizeof(AVFrame); + *(AVFrame*)data = s->frame; + + /* report that the buffer was completely consumed */ + return buf_size; +} + +static int aasc_decode_end(AVCodecContext *avctx) +{ + AascContext *s = (AascContext *)avctx->priv_data; + + /* release the last frame */ + if (s->frame.data[0]) + avctx->release_buffer(avctx, &s->frame); + + return 0; +} + +AVCodec aasc_decoder = { + "aasc", + CODEC_TYPE_VIDEO, + CODEC_ID_AASC, + sizeof(AascContext), + aasc_decode_init, + NULL, + aasc_decode_end, + aasc_decode_frame, + CODEC_CAP_DR1, +}; -- cgit v1.2.3