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)) { |
bytestream2_get_bufferu(gb, output, p2 * (depth >> 3)); |
output += p2 * (depth >> 3); |
|
// 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); |
memset(output, pix[0], p1); |
output += p1; |
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; |
} |
} |