--- /dev/null
+/*
+ * 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 <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#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,
+};
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