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Diffstat (limited to 'ffmpeg/libavcodec/msrledec.c')
-rw-r--r--ffmpeg/libavcodec/msrledec.c266
1 files changed, 266 insertions, 0 deletions
diff --git a/ffmpeg/libavcodec/msrledec.c b/ffmpeg/libavcodec/msrledec.c
new file mode 100644
index 0000000..83d7d13
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+++ b/ffmpeg/libavcodec/msrledec.c
@@ -0,0 +1,266 @@
+/*
+ * Microsoft RLE decoder
+ * Copyright (C) 2008 Konstantin Shishkov
+ *
+ * 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
+ * MS RLE decoder based on decoder by Mike Melanson and my own for TSCC
+ * For more information about the MS RLE format, visit:
+ * http://www.multimedia.cx/msrle.txt
+ */
+
+#include "libavutil/intreadwrite.h"
+#include "avcodec.h"
+#include "msrledec.h"
+
+static int msrle_decode_pal4(AVCodecContext *avctx, AVPicture *pic,
+ GetByteContext *gb)
+{
+ unsigned char rle_code;
+ unsigned char extra_byte, odd_pixel;
+ unsigned char stream_byte;
+ unsigned int pixel_ptr = 0;
+ int row_dec = pic->linesize[0];
+ int row_ptr = (avctx->height - 1) * row_dec;
+ int frame_size = row_dec * avctx->height;
+ int i;
+
+ while (row_ptr >= 0) {
+ if (bytestream2_get_bytes_left(gb) <= 0) {
+ av_log(avctx, AV_LOG_ERROR,
+ "MS RLE: bytestream overrun, %d rows left\n",
+ row_ptr);
+ return AVERROR_INVALIDDATA;
+ }
+ rle_code = stream_byte = bytestream2_get_byteu(gb);
+ if (rle_code == 0) {
+ /* fetch the next byte to see how to handle escape code */
+ stream_byte = bytestream2_get_byte(gb);
+ 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 0;
+ } else if (stream_byte == 2) {
+ /* reposition frame decode coordinates */
+ stream_byte = bytestream2_get_byte(gb);
+ pixel_ptr += stream_byte;
+ stream_byte = bytestream2_get_byte(gb);
+ 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 ||
+ bytestream2_get_bytes_left(gb) < rle_code) {
+ av_log(avctx, AV_LOG_ERROR,
+ "MS RLE: frame/stream ptr just went out of bounds (copy)\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+ for (i = 0; i < rle_code; i++) {
+ if (pixel_ptr >= avctx->width)
+ break;
+ stream_byte = bytestream2_get_byteu(gb);
+ pic->data[0][row_ptr + pixel_ptr] = stream_byte >> 4;
+ pixel_ptr++;
+ if (i + 1 == rle_code && odd_pixel)
+ break;
+ if (pixel_ptr >= avctx->width)
+ break;
+ pic->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)
+ bytestream2_skip(gb, 1);
+ }
+ } else {
+ // decode a run of data
+ if (row_ptr + pixel_ptr + stream_byte > frame_size) {
+ av_log(avctx, AV_LOG_ERROR,
+ "MS RLE: frame ptr just went out of bounds (run)\n");
+ return AVERROR_INVALIDDATA;
+ }
+ stream_byte = bytestream2_get_byte(gb);
+ for (i = 0; i < rle_code; i++) {
+ if (pixel_ptr >= avctx->width)
+ break;
+ if ((i & 1) == 0)
+ pic->data[0][row_ptr + pixel_ptr] = stream_byte >> 4;
+ else
+ pic->data[0][row_ptr + pixel_ptr] = stream_byte & 0x0F;
+ pixel_ptr++;
+ }
+ }
+ }
+
+ /* one last sanity check on the way out */
+ if (bytestream2_get_bytes_left(gb)) {
+ av_log(avctx, AV_LOG_ERROR,
+ "MS RLE: ended frame decode with %d bytes left over\n",
+ bytestream2_get_bytes_left(gb));
+ return AVERROR_INVALIDDATA;
+ }
+
+ return 0;
+}
+
+
+static int msrle_decode_8_16_24_32(AVCodecContext *avctx, AVPicture *pic,
+ int depth, GetByteContext *gb)
+{
+ uint8_t *output, *output_end;
+ int p1, p2, line=avctx->height - 1, pos=0, i;
+ uint16_t pix16;
+ uint32_t pix32;
+ unsigned int width= FFABS(pic->linesize[0]) / (depth >> 3);
+
+ output = pic->data[0] + (avctx->height - 1) * pic->linesize[0];
+ output_end = output + FFABS(pic->linesize[0]);
+
+ while (bytestream2_get_bytes_left(gb) > 0) {
+ p1 = bytestream2_get_byteu(gb);
+ if(p1 == 0) { //Escape code
+ p2 = bytestream2_get_byte(gb);
+ if(p2 == 0) { //End-of-line
+ if (--line < 0) {
+ if (bytestream2_get_be16(gb) == 1) { // end-of-picture
+ return 0;
+ } else {
+ av_log(avctx, AV_LOG_ERROR,
+ "Next line is beyond picture bounds (%d bytes left)\n",
+ bytestream2_get_bytes_left(gb));
+ return AVERROR_INVALIDDATA;
+ }
+ }
+ output = pic->data[0] + line * pic->linesize[0];
+ output_end = output + FFABS(pic->linesize[0]);
+ pos = 0;
+ continue;
+ } else if(p2 == 1) { //End-of-picture
+ return 0;
+ } else if(p2 == 2) { //Skip
+ p1 = bytestream2_get_byte(gb);
+ p2 = bytestream2_get_byte(gb);
+ line -= p2;
+ pos += p1;
+ if (line < 0 || pos >= width){
+ av_log(avctx, AV_LOG_ERROR, "Skip beyond picture bounds\n");
+ return -1;
+ }
+ output = pic->data[0] + line * pic->linesize[0] + pos * (depth >> 3);
+ output_end = pic->data[0] + line * pic->linesize[0] + FFABS(pic->linesize[0]);
+ continue;
+ }
+ // Copy data
+ if (output + p2 * (depth >> 3) > output_end) {
+ bytestream2_skip(gb, 2 * (depth >> 3));
+ continue;
+ } else if (bytestream2_get_bytes_left(gb) < p2 * (depth >> 3)) {
+ av_log(avctx, AV_LOG_ERROR, "bytestream overrun\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+ if ((depth == 8) || (depth == 24)) {
+ for(i = 0; i < p2 * (depth >> 3); i++) {
+ *output++ = bytestream2_get_byteu(gb);
+ }
+ // RLE8 copy is actually padded - and runs are not!
+ if(depth == 8 && (p2 & 1)) {
+ bytestream2_skip(gb, 1);
+ }
+ } else if (depth == 16) {
+ for(i = 0; i < p2; i++) {
+ *(uint16_t*)output = bytestream2_get_le16u(gb);
+ output += 2;
+ }
+ } else if (depth == 32) {
+ for(i = 0; i < p2; i++) {
+ *(uint32_t*)output = bytestream2_get_le32u(gb);
+ output += 4;
+ }
+ }
+ pos += p2;
+ } else { //run of pixels
+ uint8_t pix[3]; //original pixel
+ if (output + p1 * (depth >> 3) > output_end)
+ continue;
+
+ switch(depth){
+ case 8:
+ pix[0] = bytestream2_get_byte(gb);
+ for(i = 0; i < p1; i++)
+ *output++ = pix[0];
+ break;
+ case 16:
+ pix16 = bytestream2_get_le16(gb);
+ for(i = 0; i < p1; i++) {
+ *(uint16_t*)output = pix16;
+ output += 2;
+ }
+ break;
+ case 24:
+ pix[0] = bytestream2_get_byte(gb);
+ pix[1] = bytestream2_get_byte(gb);
+ pix[2] = bytestream2_get_byte(gb);
+ for(i = 0; i < p1; i++) {
+ *output++ = pix[0];
+ *output++ = pix[1];
+ *output++ = pix[2];
+ }
+ break;
+ case 32:
+ pix32 = bytestream2_get_le32(gb);
+ for(i = 0; i < p1; i++) {
+ *(uint32_t*)output = pix32;
+ output += 4;
+ }
+ break;
+ }
+ pos += p1;
+ }
+ }
+
+ av_log(avctx, AV_LOG_WARNING, "MS RLE warning: no end-of-picture code\n");
+ return 0;
+}
+
+
+int ff_msrle_decode(AVCodecContext *avctx, AVPicture *pic,
+ int depth, GetByteContext *gb)
+{
+ switch(depth){
+ case 4:
+ return msrle_decode_pal4(avctx, pic, gb);
+ case 8:
+ case 16:
+ case 24:
+ case 32:
+ return msrle_decode_8_16_24_32(avctx, pic, depth, gb);
+ default:
+ av_log(avctx, AV_LOG_ERROR, "Unknown depth %d\n", depth);
+ return -1;
+ }
+}
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