diff options
Diffstat (limited to 'libavcodec/faxcompr.c')
| -rw-r--r-- | libavcodec/faxcompr.c | 182 |
1 files changed, 147 insertions, 35 deletions
diff --git a/libavcodec/faxcompr.c b/libavcodec/faxcompr.c index 0a079fc..2a1d2bc 100644 --- a/libavcodec/faxcompr.c +++ b/libavcodec/faxcompr.c @@ -2,20 +2,20 @@ * CCITT Fax Group 3 and 4 decompression * Copyright (c) 2008 Konstantin Shishkov * - * This file is part of Libav. + * This file is part of FFmpeg. * - * Libav is free software; you can redistribute it and/or + * 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. * - * Libav is distributed in the hope that it will be useful, + * 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 Libav; if not, write to the Free Software + * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ @@ -25,9 +25,8 @@ * @author Konstantin Shishkov */ #include "avcodec.h" -#include "bitstream.h" +#include "get_bits.h" #include "put_bits.h" -#include "vlc.h" #include "faxcompr.h" #define CCITT_SYMS 104 @@ -123,8 +122,83 @@ av_cold void ff_ccitt_unpack_init(void) initialized = 1; } +static int decode_uncompressed(AVCodecContext *avctx, GetBitContext *gb, + unsigned int *pix_left, int **runs, + const int *runend, int *mode) +{ + int eob = 0; + int newmode; + int saved_run = 0; + + do { + int cwi, k; + int cw = 0; + int codes[2]; + do { + cwi = show_bits(gb, 11); + if (!cwi) { + av_log(avctx, AV_LOG_ERROR, "Invalid uncompressed codeword\n"); + return AVERROR_INVALIDDATA; + } + cwi = 10 - av_log2(cwi); + skip_bits(gb, cwi + 1); + if (cwi > 5) { + newmode = get_bits1(gb); + eob = 1; + cwi -= 6; + } + cw += cwi; + } while(cwi == 5); + + codes[0] = cw; + codes[1] = !eob; + + for (k = 0; k < 2; k++) { + if (codes[k]) { + if (*mode == !k) { + *(*runs)++ = saved_run; + if (*runs >= runend) { + av_log(avctx, AV_LOG_ERROR, "uncompressed run overrun\n"); + return AVERROR_INVALIDDATA; + } + if (*pix_left <= saved_run) { + av_log(avctx, AV_LOG_ERROR, "uncompressed run went out of bounds\n"); + return AVERROR_INVALIDDATA; + } + *pix_left -= saved_run; + saved_run = 0; + *mode = !*mode; + } + saved_run += codes[k]; + } + } + } while (!eob); + *(*runs)++ = saved_run; + if (*runs >= runend) { + av_log(avctx, AV_LOG_ERROR, "uncompressed run overrun\n"); + return AVERROR_INVALIDDATA; + } + if (*pix_left <= saved_run) { + if (*pix_left == saved_run) + return 1; + av_log(avctx, AV_LOG_ERROR, "uncompressed run went out of boundsE\n"); + return AVERROR_INVALIDDATA; + } + *pix_left -= saved_run; + saved_run = 0; + *mode = !*mode; + if (newmode != *mode) { //FIXME CHECK + *(*runs)++ = 0; + if (*runs >= runend) { + av_log(avctx, AV_LOG_ERROR, "uncompressed run overrun\n"); + return AVERROR_INVALIDDATA; + } + *mode = newmode; + } + return 0; +} -static int decode_group3_1d_line(AVCodecContext *avctx, BitstreamContext *bc, +static int decode_group3_1d_line(AVCodecContext *avctx, GetBitContext *gb, unsigned int pix_left, int *runs, const int *runend) { @@ -132,7 +206,7 @@ static int decode_group3_1d_line(AVCodecContext *avctx, BitstreamContext *bc, unsigned int run = 0; unsigned int t; for (;;) { - t = bitstream_read_vlc(bc, ccitt_vlc[mode].table, 9, 2); + t = get_vlc2(gb, ccitt_vlc[mode].table, 9, 2); run += t; if (t < 64) { *runs++ = run; @@ -150,15 +224,25 @@ static int decode_group3_1d_line(AVCodecContext *avctx, BitstreamContext *bc, run = 0; mode = !mode; } else if ((int)t == -1) { - av_log(avctx, AV_LOG_ERROR, "Incorrect code\n"); - return AVERROR_INVALIDDATA; + if (show_bits(gb, 12) == 15) { + int ret; + skip_bits(gb, 12); + ret = decode_uncompressed(avctx, gb, &pix_left, &runs, runend, &mode); + if (ret < 0) { + return ret; + } else if (ret) + break; + } else { + av_log(avctx, AV_LOG_ERROR, "Incorrect code\n"); + return AVERROR_INVALIDDATA; + } } } *runs++ = 0; return 0; } -static int decode_group3_2d_line(AVCodecContext *avctx, BitstreamContext *bc, +static int decode_group3_2d_line(AVCodecContext *avctx, GetBitContext *gb, unsigned int width, int *runs, const int *runend, const int *ref) { @@ -166,19 +250,19 @@ static int decode_group3_2d_line(AVCodecContext *avctx, BitstreamContext *bc, int run_off = *ref++; unsigned int offs = 0, run = 0; - runend--; // for the last written 0 - while (offs < width) { - int cmode = bitstream_read_vlc(bc, ccitt_group3_2d_vlc.table, 9, 1); + int cmode = get_vlc2(gb, ccitt_group3_2d_vlc.table, 9, 1); if (cmode == -1) { av_log(avctx, AV_LOG_ERROR, "Incorrect mode VLC\n"); return AVERROR_INVALIDDATA; } if (!cmode) { //pass mode - run_off += *ref++; + if (run_off < width) + run_off += *ref++; run = run_off - offs; offs = run_off; - run_off += *ref++; + if (run_off < width) + run_off += *ref++; if (offs > width) { av_log(avctx, AV_LOG_ERROR, "Run went out of bounds\n"); return AVERROR_INVALIDDATA; @@ -189,7 +273,7 @@ static int decode_group3_2d_line(AVCodecContext *avctx, BitstreamContext *bc, for (k = 0; k < 2; k++) { run = 0; for (;;) { - t = bitstream_read_vlc(bc, ccitt_vlc[mode].table, 9, 2); + t = get_vlc2(gb, ccitt_vlc[mode].table, 9, 2); if (t == -1) { av_log(avctx, AV_LOG_ERROR, "Incorrect code\n"); return AVERROR_INVALIDDATA; @@ -212,8 +296,25 @@ static int decode_group3_2d_line(AVCodecContext *avctx, BitstreamContext *bc, mode = !mode; } } else if (cmode == 9 || cmode == 10) { - avpriv_report_missing_feature(avctx, "Special modes support"); - return AVERROR_PATCHWELCOME; + int xxx = get_bits(gb, 3); + if (cmode == 9 && xxx == 7) { + int ret; + int pix_left = width - offs; + + if (saved_run) { + av_log(avctx, AV_LOG_ERROR, "saved run %d on entering uncompressed mode\n", saved_run); + return AVERROR_INVALIDDATA; + } + ret = decode_uncompressed(avctx, gb, &pix_left, &runs, runend, &mode); + offs = width - pix_left; + if (ret < 0) { + return ret; + } else if (ret) + break; + } else { + avpriv_report_missing_feature(avctx, "Special mode %d xxx=%d support", cmode, xxx); + return AVERROR_PATCHWELCOME; + } } else { //vertical mode run = run_off - offs + (cmode - 5); run_off -= *--ref; @@ -231,13 +332,19 @@ static int decode_group3_2d_line(AVCodecContext *avctx, BitstreamContext *bc, mode = !mode; } //sync line pointers - while (run_off <= offs) { + while (offs < width && run_off <= offs) { run_off += *ref++; run_off += *ref++; } } *runs++ = saved_run; - *runs++ = 0; + if (saved_run) { + if (runs >= runend) { + av_log(avctx, AV_LOG_ERROR, "Run overrun\n"); + return -1; + } + *runs++ = 0; + } return 0; } @@ -246,7 +353,7 @@ static void put_line(uint8_t *dst, int size, int width, const int *runs) PutBitContext pb; int run, mode = ~0, pix_left = width, run_idx = 0; - init_put_bits(&pb, dst, size * 8); + init_put_bits(&pb, dst, size); while (pix_left > 0) { run = runs[run_idx++]; mode = ~mode; @@ -259,12 +366,12 @@ static void put_line(uint8_t *dst, int size, int width, const int *runs) flush_put_bits(&pb); } -static int find_group3_syncmarker(BitstreamContext *bc, int srcsize) +static int find_group3_syncmarker(GetBitContext *gb, int srcsize) { unsigned int state = -1; - srcsize -= bitstream_tell(bc); + srcsize -= get_bits_count(gb); while (srcsize-- > 0) { - state += state + bitstream_read_bit(bc); + state += state + get_bits1(gb); if ((state & 0xFFF) == 1) return 0; } @@ -276,13 +383,14 @@ int ff_ccitt_unpack(AVCodecContext *avctx, const uint8_t *src, int srcsize, enum TiffCompr compr, int opts) { int j; - BitstreamContext bc; + GetBitContext gb; int *runs, *ref = NULL, *runend; int ret; int runsize = avctx->width + 2; + int has_eol; - runs = av_malloc(runsize * sizeof(runs[0])); - ref = av_malloc(runsize * sizeof(ref[0])); + runs = av_malloc_array(runsize, sizeof(runs[0])); + ref = av_malloc_array(runsize, sizeof(ref[0])); if (!runs || !ref) { ret = AVERROR(ENOMEM); goto fail; @@ -290,27 +398,31 @@ int ff_ccitt_unpack(AVCodecContext *avctx, const uint8_t *src, int srcsize, ref[0] = avctx->width; ref[1] = 0; ref[2] = 0; - bitstream_init8(&bc, src, srcsize); + if ((ret = init_get_bits8(&gb, src, srcsize)) < 0) + goto fail; + has_eol = show_bits(&gb, 12) == 1 || show_bits(&gb, 16) == 1; + for (j = 0; j < height; j++) { runend = runs + runsize; if (compr == TIFF_G4) { - ret = decode_group3_2d_line(avctx, &bc, avctx->width, runs, runend, + ret = decode_group3_2d_line(avctx, &gb, avctx->width, runs, runend, ref); if (ret < 0) goto fail; } else { int g3d1 = (compr == TIFF_G3) && !(opts & 1); if (compr != TIFF_CCITT_RLE && - find_group3_syncmarker(&bc, srcsize * 8) < 0) + has_eol && + find_group3_syncmarker(&gb, srcsize * 8) < 0) break; - if (compr == TIFF_CCITT_RLE || g3d1 || bitstream_read_bit(&bc)) - ret = decode_group3_1d_line(avctx, &bc, avctx->width, runs, + if (compr == TIFF_CCITT_RLE || g3d1 || get_bits1(&gb)) + ret = decode_group3_1d_line(avctx, &gb, avctx->width, runs, runend); else - ret = decode_group3_2d_line(avctx, &bc, avctx->width, runs, + ret = decode_group3_2d_line(avctx, &gb, avctx->width, runs, runend, ref); if (compr == TIFF_CCITT_RLE) - bitstream_align(&bc); + align_get_bits(&gb); } if (avctx->err_recognition & AV_EF_EXPLODE && ret < 0) goto fail; |
