X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Fmmvideo.c;h=2187d7f585c2c2e9e4cce05d91f41187e30bc930;hb=9afb7061f938831248942050cfdb449e014ed427;hp=596ca7aec47b0fb8067384f5bc992c4c7a2e2836;hpb=4a49ab77c6bb2348992e1e70b14f2d1efaf7ddbb;p=ffmpeg diff --git a/libavcodec/mmvideo.c b/libavcodec/mmvideo.c index 596ca7aec47..2187d7f585c 100644 --- a/libavcodec/mmvideo.c +++ b/libavcodec/mmvideo.c @@ -2,27 +2,27 @@ * American Laser Games MM Video Decoder * Copyright (c) 2006,2008 Peter Ross * - * This file is part of FFmpeg. + * This file is part of Libav. * - * FFmpeg is free software; you can redistribute it and/or + * Libav 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, + * Libav 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 + * License along with Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** - * @file libavcodec/mmvideo.c + * @file * American Laser Games MM Video Decoder - * by Peter Ross (suxen_drol at hotmail dot com) + * by Peter Ross (pross@xvid.org) * * The MM format was used by IBM-PC ports of ALG's "arcade shooter" games, * including Mad Dog McCree and Crime Patrol. @@ -33,6 +33,7 @@ #include "libavutil/intreadwrite.h" #include "avcodec.h" +#include "bytestream.h" #define MM_PREAMBLE_SIZE 6 @@ -48,6 +49,7 @@ typedef struct MmContext { AVCodecContext *avctx; AVFrame frame; int palette[AVPALETTE_COUNT]; + GetByteContext gb; } MmContext; static av_cold int mm_decode_init(AVCodecContext *avctx) @@ -59,41 +61,43 @@ static av_cold int mm_decode_init(AVCodecContext *avctx) avctx->pix_fmt = PIX_FMT_PAL8; s->frame.reference = 1; - if (avctx->get_buffer(avctx, &s->frame)) { - av_log(s->avctx, AV_LOG_ERROR, "mmvideo: get_buffer() failed\n"); - return -1; - } return 0; } -static void mm_decode_pal(MmContext *s, const uint8_t *buf, const uint8_t *buf_end) +static int mm_decode_pal(MmContext *s) { int i; - buf += 4; - for (i=0; i<128 && buf+2palette[i] = AV_RB24(buf); + + bytestream2_skip(&s->gb, 4); + for (i = 0; i < 128; i++) { + s->palette[i] = bytestream2_get_be24(&s->gb); s->palette[i+128] = s->palette[i]<<2; - buf += 3; } + + return 0; } -static void mm_decode_intra(MmContext * s, int half_horiz, int half_vert, const uint8_t *buf, int buf_size) +/** + * @param half_horiz Half horizontal resolution (0 or 1) + * @param half_vert Half vertical resolution (0 or 1) + */ +static int mm_decode_intra(MmContext * s, int half_horiz, int half_vert) { - int i, x, y; - i=0; x=0; y=0; + int x = 0, y = 0; - while(igb) > 0) { int run_length, color; - if (buf[i] & 0x80) { + if (y >= s->avctx->height) + return 0; + + color = bytestream2_get_byte(&s->gb); + if (color & 0x80) { run_length = 1; - color = buf[i]; - i++; }else{ - run_length = (buf[i] & 0x7f) + 2; - color = buf[i+1]; - i+=2; + run_length = (color & 0x7f) + 2; + color = bytestream2_get_byte(&s->gb); } if (half_horiz) @@ -108,33 +112,46 @@ static void mm_decode_intra(MmContext * s, int half_horiz, int half_vert, const if (x >= s->avctx->width) { x=0; - y += half_vert ? 2 : 1; + y += 1 + half_vert; } } + + return 0; } -static void mm_decode_inter(MmContext * s, int half_horiz, int half_vert, const uint8_t *buf, int buf_size) +/* + * @param half_horiz Half horizontal resolution (0 or 1) + * @param half_vert Half vertical resolution (0 or 1) + */ +static int mm_decode_inter(MmContext * s, int half_horiz, int half_vert) { - const int data_ptr = 2 + AV_RL16(&buf[0]); - int d, r, y; - d = data_ptr; r = 2; y = 0; + int data_off = bytestream2_get_le16(&s->gb), y; + GetByteContext data_ptr; + + if (bytestream2_get_bytes_left(&s->gb) < data_off) + return AVERROR_INVALIDDATA; - while(r < data_ptr) { + bytestream2_init(&data_ptr, s->gb.buffer + data_off, bytestream2_get_bytes_left(&s->gb) - data_off); + while (s->gb.buffer < data_ptr.buffer_start) { int i, j; - int length = buf[r] & 0x7f; - int x = buf[r+1] + ((buf[r] & 0x80) << 1); - r += 2; + int length = bytestream2_get_byte(&s->gb); + int x = bytestream2_get_byte(&s->gb) + ((length & 0x80) << 1); + length &= 0x7F; if (length==0) { y += x; continue; } + if (y + half_vert >= s->avctx->height) + return 0; + for(i=0; igb); for(j=0; j<8; j++) { - int replace = (buf[r+i] >> (7-j)) & 1; + int replace = (replace_array >> (7-j)) & 1; if (replace) { - int color = buf[d]; + int color = bytestream2_get_byte(&data_ptr); s->frame.data[0][y*s->frame.linesize[0] + x] = color; if (half_horiz) s->frame.data[0][y*s->frame.linesize[0] + x + 1] = color; @@ -143,15 +160,15 @@ static void mm_decode_inter(MmContext * s, int half_horiz, int half_vert, const if (half_horiz) s->frame.data[0][(y+1)*s->frame.linesize[0] + x + 1] = color; } - d++; } - x += half_horiz ? 2 : 1; + x += 1 + half_horiz; } } - r += length; - y += half_vert ? 2 : 1; + y += 1 + half_vert; } + + return 0; } static int mm_decode_frame(AVCodecContext *avctx, @@ -161,25 +178,35 @@ static int mm_decode_frame(AVCodecContext *avctx, const uint8_t *buf = avpkt->data; int buf_size = avpkt->size; MmContext *s = avctx->priv_data; - const uint8_t *buf_end = buf+buf_size; - int type; + int type, res; + if (buf_size < MM_PREAMBLE_SIZE) + return AVERROR_INVALIDDATA; type = AV_RL16(&buf[0]); buf += MM_PREAMBLE_SIZE; buf_size -= MM_PREAMBLE_SIZE; + bytestream2_init(&s->gb, buf, buf_size); - switch(type) { - case MM_TYPE_PALETTE : mm_decode_pal(s, buf, buf_end); return buf_size; - case MM_TYPE_INTRA : mm_decode_intra(s, 0, 0, buf, buf_size); break; - case MM_TYPE_INTRA_HH : mm_decode_intra(s, 1, 0, buf, buf_size); break; - case MM_TYPE_INTRA_HHV : mm_decode_intra(s, 1, 1, buf, buf_size); break; - case MM_TYPE_INTER : mm_decode_inter(s, 0, 0, buf, buf_size); break; - case MM_TYPE_INTER_HH : mm_decode_inter(s, 1, 0, buf, buf_size); break; - case MM_TYPE_INTER_HHV : mm_decode_inter(s, 1, 1, buf, buf_size); break; - default : + if (avctx->reget_buffer(avctx, &s->frame) < 0) { + av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n"); return -1; } + switch(type) { + case MM_TYPE_PALETTE : res = mm_decode_pal(s); return buf_size; + case MM_TYPE_INTRA : res = mm_decode_intra(s, 0, 0); break; + case MM_TYPE_INTRA_HH : res = mm_decode_intra(s, 1, 0); break; + case MM_TYPE_INTRA_HHV : res = mm_decode_intra(s, 1, 1); break; + case MM_TYPE_INTER : res = mm_decode_inter(s, 0, 0); break; + case MM_TYPE_INTER_HH : res = mm_decode_inter(s, 1, 0); break; + case MM_TYPE_INTER_HHV : res = mm_decode_inter(s, 1, 1); break; + default: + res = AVERROR_INVALIDDATA; + break; + } + if (res < 0) + return res; + memcpy(s->frame.data[1], s->palette, AVPALETTE_SIZE); *data_size = sizeof(AVFrame); @@ -198,15 +225,14 @@ static av_cold int mm_decode_end(AVCodecContext *avctx) return 0; } -AVCodec mmvideo_decoder = { - "mmvideo", - CODEC_TYPE_VIDEO, - CODEC_ID_MMVIDEO, - sizeof(MmContext), - mm_decode_init, - NULL, - mm_decode_end, - mm_decode_frame, - CODEC_CAP_DR1, - .long_name = NULL_IF_CONFIG_SMALL("American Laser Games MM Video"), +AVCodec ff_mmvideo_decoder = { + .name = "mmvideo", + .type = AVMEDIA_TYPE_VIDEO, + .id = AV_CODEC_ID_MMVIDEO, + .priv_data_size = sizeof(MmContext), + .init = mm_decode_init, + .close = mm_decode_end, + .decode = mm_decode_frame, + .capabilities = CODEC_CAP_DR1, + .long_name = NULL_IF_CONFIG_SMALL("American Laser Games MM Video"), };