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Diffstat (limited to 'contrib/ffmpeg/libavcodec/msrle.c')
-rw-r--r--contrib/ffmpeg/libavcodec/msrle.c309
1 files changed, 309 insertions, 0 deletions
diff --git a/contrib/ffmpeg/libavcodec/msrle.c b/contrib/ffmpeg/libavcodec/msrle.c
new file mode 100644
index 000000000..fae5616e5
--- /dev/null
+++ b/contrib/ffmpeg/libavcodec/msrle.c
@@ -0,0 +1,309 @@
+/*
+ * Micrsoft RLE Video Decoder
+ * Copyright (C) 2003 the ffmpeg project
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg 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 FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file msrle.c
+ * MS RLE Video Decoder by Mike Melanson (melanson@pcisys.net)
+ * For more information about the MS RLE format, visit:
+ * http://www.pcisys.net/~melanson/codecs/
+ *
+ * The MS RLE decoder outputs PAL8 colorspace data.
+ *
+ * Note that this decoder expects the palette colors from the end of the
+ * BITMAPINFO header passed through palctrl.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "common.h"
+#include "avcodec.h"
+#include "dsputil.h"
+
+typedef struct MsrleContext {
+ AVCodecContext *avctx;
+ AVFrame frame;
+
+ unsigned char *buf;
+ int size;
+
+} MsrleContext;
+
+#define FETCH_NEXT_STREAM_BYTE() \
+ if (stream_ptr >= s->size) \
+ { \
+ av_log(s->avctx, AV_LOG_ERROR, " MS RLE: stream ptr just went out of bounds (1)\n"); \
+ return; \
+ } \
+ stream_byte = s->buf[stream_ptr++];
+
+static void msrle_decode_pal4(MsrleContext *s)
+{
+ int stream_ptr = 0;
+ unsigned char rle_code;
+ unsigned char extra_byte, odd_pixel;
+ unsigned char stream_byte;
+ int pixel_ptr = 0;
+ int row_dec = s->frame.linesize[0];
+ int row_ptr = (s->avctx->height - 1) * row_dec;
+ int frame_size = row_dec * s->avctx->height;
+ int i;
+
+ /* make the palette available */
+ memcpy(s->frame.data[1], s->avctx->palctrl->palette, AVPALETTE_SIZE);
+ if (s->avctx->palctrl->palette_changed) {
+ s->frame.palette_has_changed = 1;
+ s->avctx->palctrl->palette_changed = 0;
+ }
+
+ 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 */
+ return;
+ } 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
+ odd_pixel = stream_byte & 1;
+ rle_code = (stream_byte + 1) / 2;
+ extra_byte = rle_code & 0x01;
+ if ((row_ptr + pixel_ptr + stream_byte > frame_size) ||
+ (row_ptr < 0)) {
+ av_log(s->avctx, AV_LOG_ERROR, " MS RLE: frame ptr just went out of bounds (1)\n");
+ return;
+ }
+
+ for (i = 0; i < rle_code; i++) {
+ if (pixel_ptr >= s->avctx->width)
+ break;
+ FETCH_NEXT_STREAM_BYTE();
+ s->frame.data[0][row_ptr + pixel_ptr] = stream_byte >> 4;
+ pixel_ptr++;
+ if (i + 1 == rle_code && odd_pixel)
+ break;
+ if (pixel_ptr >= s->avctx->width)
+ break;
+ s->frame.data[0][row_ptr + pixel_ptr] = stream_byte & 0x0F;
+ pixel_ptr++;
+ }
+
+ // if the RLE code is odd, skip a byte in the stream
+ if (extra_byte)
+ stream_ptr++;
+ }
+ } else {
+ // decode a run of data
+ if ((row_ptr + pixel_ptr + stream_byte > frame_size) ||
+ (row_ptr < 0)) {
+ av_log(s->avctx, AV_LOG_ERROR, " MS RLE: frame ptr just went out of bounds (1)\n");
+ return;
+ }
+ FETCH_NEXT_STREAM_BYTE();
+ for (i = 0; i < rle_code; i++) {
+ if (pixel_ptr >= s->avctx->width)
+ break;
+ if ((i & 1) == 0)
+ s->frame.data[0][row_ptr + pixel_ptr] = stream_byte >> 4;
+ else
+ s->frame.data[0][row_ptr + pixel_ptr] = stream_byte & 0x0F;
+ pixel_ptr++;
+ }
+ }
+ }
+
+ /* one last sanity check on the way out */
+ if (stream_ptr < s->size)
+ av_log(s->avctx, AV_LOG_ERROR, " MS RLE: ended frame decode with bytes left over (%d < %d)\n",
+ stream_ptr, s->size);
+}
+
+
+
+static void msrle_decode_pal8(MsrleContext *s)
+{
+ int stream_ptr = 0;
+ unsigned char rle_code;
+ unsigned char extra_byte;
+ unsigned char stream_byte;
+ int pixel_ptr = 0;
+ int row_dec = s->frame.linesize[0];
+ int row_ptr = (s->avctx->height - 1) * row_dec;
+ int frame_size = row_dec * s->avctx->height;
+
+ /* make the palette available */
+ memcpy(s->frame.data[1], s->avctx->palctrl->palette, AVPALETTE_SIZE);
+ if (s->avctx->palctrl->palette_changed) {
+ s->frame.palette_has_changed = 1;
+ s->avctx->palctrl->palette_changed = 0;
+ }
+
+ 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 */
+ return;
+ } 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 ((row_ptr + pixel_ptr + stream_byte > frame_size) ||
+ (row_ptr < 0)) {
+ av_log(s->avctx, AV_LOG_ERROR, " MS RLE: frame ptr just went out of bounds (1)\n");
+ return;
+ }
+
+ rle_code = stream_byte;
+ extra_byte = stream_byte & 0x01;
+ if (stream_ptr + rle_code + extra_byte > s->size) {
+ av_log(s->avctx, AV_LOG_ERROR, " MS RLE: stream ptr just went out of bounds (2)\n");
+ return;
+ }
+
+ while (rle_code--) {
+ FETCH_NEXT_STREAM_BYTE();
+ s->frame.data[0][row_ptr + pixel_ptr] = stream_byte;
+ pixel_ptr++;
+ }
+
+ /* if the RLE code is odd, skip a byte in the stream */
+ if (extra_byte)
+ stream_ptr++;
+ }
+ } else {
+ /* decode a run of data */
+ if ((row_ptr + pixel_ptr + stream_byte > frame_size) ||
+ (row_ptr < 0)) {
+ av_log(s->avctx, AV_LOG_ERROR, " MS RLE: frame ptr just went out of bounds (2)\n");
+ return;
+ }
+
+ 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 < s->size)
+ av_log(s->avctx, AV_LOG_ERROR, " MS RLE: ended frame decode with bytes left over (%d < %d)\n",
+ stream_ptr, s->size);
+}
+
+static int msrle_decode_init(AVCodecContext *avctx)
+{
+ MsrleContext *s = (MsrleContext *)avctx->priv_data;
+
+ s->avctx = avctx;
+
+ avctx->pix_fmt = PIX_FMT_PAL8;
+ avctx->has_b_frames = 0;
+ s->frame.data[0] = NULL;
+
+ return 0;
+}
+
+static int msrle_decode_frame(AVCodecContext *avctx,
+ void *data, int *data_size,
+ uint8_t *buf, int buf_size)
+{
+ MsrleContext *s = (MsrleContext *)avctx->priv_data;
+
+ s->buf = buf;
+ s->size = buf_size;
+
+ 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;
+ }
+
+ switch (avctx->bits_per_sample) {
+ case 8:
+ msrle_decode_pal8(s);
+ break;
+ case 4:
+ msrle_decode_pal4(s);
+ break;
+ default:
+ av_log(avctx, AV_LOG_ERROR, "Don't know how to decode depth %u.\n",
+ avctx->bits_per_sample);
+ }
+
+ *data_size = sizeof(AVFrame);
+ *(AVFrame*)data = s->frame;
+
+ /* report that the buffer was completely consumed */
+ return buf_size;
+}
+
+static int msrle_decode_end(AVCodecContext *avctx)
+{
+ MsrleContext *s = (MsrleContext *)avctx->priv_data;
+
+ /* release the last frame */
+ if (s->frame.data[0])
+ avctx->release_buffer(avctx, &s->frame);
+
+ return 0;
+}
+
+AVCodec msrle_decoder = {
+ "msrle",
+ CODEC_TYPE_VIDEO,
+ CODEC_ID_MSRLE,
+ sizeof(MsrleContext),
+ msrle_decode_init,
+ NULL,
+ msrle_decode_end,
+ msrle_decode_frame,
+ CODEC_CAP_DR1,
+};
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