| /* |
| * Microsoft Paint (MSP) version 2 decoder |
| * Copyright (c) 2020 Peter Ross (pross@xvid.org) |
| * |
| * 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 |
| * Microsoft Paint (MSP) version 2 decoder |
| */ |
| |
| #include "avcodec.h" |
| #include "bytestream.h" |
| #include "internal.h" |
| |
| static int msp2_decode_frame(AVCodecContext *avctx, |
| void *data, int *got_frame, |
| AVPacket *avpkt) |
| { |
| const uint8_t *buf = avpkt->data; |
| int buf_size = avpkt->size; |
| AVFrame *p = data; |
| int ret; |
| unsigned int x, y, width = (avctx->width + 7) / 8; |
| GetByteContext idx, gb; |
| |
| if (buf_size <= 2 * avctx->height) |
| return AVERROR_INVALIDDATA; |
| |
| avctx->pix_fmt = AV_PIX_FMT_MONOBLACK; |
| |
| if ((ret = ff_get_buffer(avctx, p, 0)) < 0) |
| return ret; |
| |
| p->pict_type = AV_PICTURE_TYPE_I; |
| p->key_frame = 1; |
| |
| bytestream2_init(&idx, buf, 2 * avctx->height); |
| buf += 2 * avctx->height; |
| buf_size -= 2 * avctx->height; |
| |
| for (y = 0; y < avctx->height; y++) { |
| unsigned int pkt_size = bytestream2_get_le16(&idx); |
| if (!pkt_size) { |
| memset(p->data[0] + y * p->linesize[0], 0xFF, width); |
| continue; |
| } |
| |
| if (pkt_size > buf_size) { |
| av_log(avctx, AV_LOG_WARNING, "image probably corrupt\n"); |
| pkt_size = buf_size; |
| } |
| |
| bytestream2_init(&gb, buf, pkt_size); |
| x = 0; |
| while (bytestream2_get_bytes_left(&gb) && x < width) { |
| int size = bytestream2_get_byte(&gb); |
| if (size) { |
| memcpy(p->data[0] + y * p->linesize[0] + x, gb.buffer, FFMIN(size, width - x)); |
| bytestream2_skip(&gb, size); |
| } else { |
| int value; |
| size = bytestream2_get_byte(&gb); |
| if (!size) |
| avpriv_request_sample(avctx, "escape value"); |
| value = bytestream2_get_byte(&gb); |
| memset(p->data[0] + y * p->linesize[0] + x, value, FFMIN(size, width - x)); |
| } |
| x += size; |
| } |
| |
| buf += pkt_size; |
| buf_size -= pkt_size; |
| } |
| |
| *got_frame = 1; |
| return buf_size; |
| } |
| |
| AVCodec ff_msp2_decoder = { |
| .name = "msp2", |
| .long_name = NULL_IF_CONFIG_SMALL("Microsoft Paint (MSP) version 2"), |
| .type = AVMEDIA_TYPE_VIDEO, |
| .id = AV_CODEC_ID_MSP2, |
| .decode = msp2_decode_frame, |
| .capabilities = AV_CODEC_CAP_DR1, |
| }; |