GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavcodec/msrledec.c Lines: 109 150 72.7 %
Date: 2019-11-20 04:07:19 Branches: 68 100 68.0 %

Line Branch Exec Source
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/*
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 * Microsoft RLE decoder
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 * Copyright (C) 2008 Konstantin Shishkov
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 *
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 * This file is part of FFmpeg.
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 *
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 * FFmpeg is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * FFmpeg is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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/**
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 * @file
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 * MS RLE decoder based on decoder by Mike Melanson and my own for TSCC
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 * For more information about the MS RLE format, visit:
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 *   http://www.multimedia.cx/msrle.txt
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 */
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#include "libavutil/intreadwrite.h"
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#include "avcodec.h"
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#include "msrledec.h"
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33
2
static int msrle_decode_pal4(AVCodecContext *avctx, AVFrame *pic,
34
                             GetByteContext *gb)
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{
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    unsigned char rle_code;
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    unsigned char extra_byte, odd_pixel;
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    unsigned char stream_byte;
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2
    int pixel_ptr = 0;
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2
    int line = avctx->height - 1;
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    int i;
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43

754
    while (line >= 0 && pixel_ptr <= avctx->width) {
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754
        if (bytestream2_get_bytes_left(gb) <= 0) {
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            av_log(avctx, AV_LOG_ERROR,
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                   "MS RLE: bytestream overrun, %dx%d left\n",
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                   avctx->width - pixel_ptr, line);
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            return AVERROR_INVALIDDATA;
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        }
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754
        rle_code = stream_byte = bytestream2_get_byteu(gb);
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754
        if (rle_code == 0) {
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            /* fetch the next byte to see how to handle escape code */
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138
            stream_byte = bytestream2_get_byte(gb);
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138
            if (stream_byte == 0) {
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                /* line is done, goto the next one */
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126
                line--;
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126
                pixel_ptr = 0;
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12
            } else if (stream_byte == 1) {
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                /* decode is done */
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2
                return 0;
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10
            } else if (stream_byte == 2) {
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                /* reposition frame decode coordinates */
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                stream_byte = bytestream2_get_byte(gb);
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                pixel_ptr += stream_byte;
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                stream_byte = bytestream2_get_byte(gb);
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                line -= stream_byte;
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            } else {
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                // copy pixels from encoded stream
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10
                odd_pixel =  stream_byte & 1;
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10
                rle_code = (stream_byte + 1) / 2;
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10
                extra_byte = rle_code & 0x01;
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10
                if (pixel_ptr + 2*rle_code - odd_pixel > avctx->width ||
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10
                    bytestream2_get_bytes_left(gb) < rle_code) {
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                    av_log(avctx, AV_LOG_ERROR,
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                           "MS RLE: frame/stream ptr just went out of bounds (copy)\n");
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                    return AVERROR_INVALIDDATA;
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                }
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100
                for (i = 0; i < rle_code; i++) {
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90
                    if (pixel_ptr >= avctx->width)
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                        break;
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90
                    stream_byte = bytestream2_get_byteu(gb);
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90
                    pic->data[0][line * pic->linesize[0] + pixel_ptr] = stream_byte >> 4;
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90
                    pixel_ptr++;
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90
                    if (i + 1 == rle_code && odd_pixel)
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                        break;
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90
                    if (pixel_ptr >= avctx->width)
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                        break;
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90
                    pic->data[0][line * pic->linesize[0] + pixel_ptr] = stream_byte & 0x0F;
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90
                    pixel_ptr++;
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                }
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                // if the RLE code is odd, skip a byte in the stream
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10
                if (extra_byte)
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10
                    bytestream2_skip(gb, 1);
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            }
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        } else {
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            // decode a run of data
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616
            if (pixel_ptr + rle_code > avctx->width + 1) {
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                av_log(avctx, AV_LOG_ERROR,
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                       "MS RLE: frame ptr just went out of bounds (run) %d %d %d\n", pixel_ptr, rle_code, avctx->width);
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                return AVERROR_INVALIDDATA;
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            }
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616
            stream_byte = bytestream2_get_byte(gb);
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16692
            for (i = 0; i < rle_code; i++) {
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16204
                if (pixel_ptr >= avctx->width)
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128
                    break;
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16076
                if ((i & 1) == 0)
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8102
                    pic->data[0][line * pic->linesize[0] + pixel_ptr] = stream_byte >> 4;
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                else
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7974
                    pic->data[0][line * pic->linesize[0] + pixel_ptr] = stream_byte & 0x0F;
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16076
                pixel_ptr++;
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            }
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        }
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    }
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    /* one last sanity check on the way out */
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    if (bytestream2_get_bytes_left(gb)) {
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        av_log(avctx, AV_LOG_ERROR,
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               "MS RLE: ended frame decode with %d bytes left over\n",
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               bytestream2_get_bytes_left(gb));
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        return AVERROR_INVALIDDATA;
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    }
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    return 0;
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}
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128
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178
static int msrle_decode_8_16_24_32(AVCodecContext *avctx, AVFrame *pic,
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                                   int depth, GetByteContext *gb)
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{
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    uint8_t *output, *output_end;
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178
    int p1, p2, line=avctx->height - 1, pos=0, i;
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    uint16_t pix16;
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    uint32_t pix32;
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178
    unsigned int width= FFABS(pic->linesize[0]) / (depth >> 3);
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138
178
    output     = pic->data[0] + (avctx->height - 1) * pic->linesize[0];
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178
    output_end = output + FFABS(pic->linesize[0]);
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141
130532
    while (bytestream2_get_bytes_left(gb) > 0) {
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130532
        p1 = bytestream2_get_byteu(gb);
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130532
        if(p1 == 0) { //Escape code
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58128
            p2 = bytestream2_get_byte(gb);
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58128
            if(p2 == 0) { //End-of-line
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9220
                if (--line < 0) {
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                    if (bytestream2_get_be16(gb) == 1) { // end-of-picture
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                        return 0;
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                    } else {
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                        av_log(avctx, AV_LOG_ERROR,
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                               "Next line is beyond picture bounds (%d bytes left)\n",
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                               bytestream2_get_bytes_left(gb));
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                        return AVERROR_INVALIDDATA;
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                    }
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                }
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9220
                output = pic->data[0] + line * pic->linesize[0];
157
9220
                output_end = output + FFABS(pic->linesize[0]);
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9220
                pos = 0;
159
9220
                continue;
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48908
            } else if(p2 == 1) { //End-of-picture
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177
                return 0;
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48731
            } else if(p2 == 2) { //Skip
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13943
                p1 = bytestream2_get_byte(gb);
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13943
                p2 = bytestream2_get_byte(gb);
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13943
                line -= p2;
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13943
                pos += p1;
167

13943
                if (line < 0 || pos >= width){
168
                    av_log(avctx, AV_LOG_ERROR, "Skip beyond picture bounds\n");
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                    return -1;
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                }
171
13943
                output = pic->data[0] + line * pic->linesize[0] + pos * (depth >> 3);
172
13943
                output_end = pic->data[0] + line * pic->linesize[0] + FFABS(pic->linesize[0]);
173
13943
                continue;
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            }
175
            // Copy data
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34788
            if (output + p2 * (depth >> 3) > output_end) {
177
                bytestream2_skip(gb, 2 * (depth >> 3));
178
                continue;
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34788
            } else if (bytestream2_get_bytes_left(gb) < p2 * (depth >> 3)) {
180
1
                av_log(avctx, AV_LOG_ERROR, "bytestream overrun\n");
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1
                return AVERROR_INVALIDDATA;
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            }
183
184

34787
            if ((depth == 8) || (depth == 24)) {
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9473
                bytestream2_get_bufferu(gb, output, p2 * (depth >> 3));
186
9473
                output += p2 * (depth >> 3);
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188
                // RLE8 copy is actually padded - and runs are not!
189

9473
                if(depth == 8 && (p2 & 1)) {
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7144
                    bytestream2_skip(gb, 1);
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                }
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25314
            } else if (depth == 16) {
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59976
                for(i = 0; i < p2; i++) {
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52629
                    *(uint16_t*)output = bytestream2_get_le16u(gb);
195
52629
                    output += 2;
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                }
197
17967
            } else if (depth == 32) {
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165584
                for(i = 0; i < p2; i++) {
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147617
                    *(uint32_t*)output = bytestream2_get_le32u(gb);
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147617
                    output += 4;
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                }
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            }
203
34787
            pos += p2;
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        } else { //run of pixels
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            uint8_t pix[3]; //original pixel
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72404
            if (output + p1 * (depth >> 3) > output_end)
207
                continue;
208
209

72404
            switch(depth){
210
11494
            case  8:
211
11494
                pix[0] = bytestream2_get_byte(gb);
212
11494
                memset(output, pix[0], p1);
213
11494
                output += p1;
214
11494
                break;
215
14196
            case 16:
216
14196
                pix16  = bytestream2_get_le16(gb);
217
715555
                for(i = 0; i < p1; i++) {
218
701359
                        *(uint16_t*)output = pix16;
219
701359
                        output += 2;
220
                }
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14196
                break;
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            case 24:
223
                pix[0] = bytestream2_get_byte(gb);
224
                pix[1] = bytestream2_get_byte(gb);
225
                pix[2] = bytestream2_get_byte(gb);
226
                for(i = 0; i < p1; i++) {
227
                        *output++ = pix[0];
228
                        *output++ = pix[1];
229
                        *output++ = pix[2];
230
                }
231
                break;
232
46714
            case 32:
233
46714
                pix32  = bytestream2_get_le32(gb);
234
1616545
                for(i = 0; i < p1; i++) {
235
1569831
                        *(uint32_t*)output = pix32;
236
1569831
                        output += 4;
237
                }
238
46714
                break;
239
            }
240
72404
            pos += p1;
241
        }
242
    }
243
244
    av_log(avctx, AV_LOG_WARNING, "MS RLE warning: no end-of-picture code\n");
245
    return 0;
246
}
247
248
249
180
int ff_msrle_decode(AVCodecContext *avctx, AVFrame *pic,
250
                    int depth, GetByteContext *gb)
251
{
252
180
    switch(depth){
253
2
    case  4:
254
2
        return msrle_decode_pal4(avctx, pic, gb);
255
178
    case  8:
256
    case 16:
257
    case 24:
258
    case 32:
259
178
        return msrle_decode_8_16_24_32(avctx, pic, depth, gb);
260
    default:
261
        av_log(avctx, AV_LOG_ERROR, "Unknown depth %d\n", depth);
262
        return -1;
263
    }
264
}