diff options
Diffstat (limited to 'ffmpeg/libavcodec/msrle.c')
| -rw-r--r-- | ffmpeg/libavcodec/msrle.c | 164 |
1 files changed, 164 insertions, 0 deletions
diff --git a/ffmpeg/libavcodec/msrle.c b/ffmpeg/libavcodec/msrle.c new file mode 100644 index 0000000..674e586 --- /dev/null +++ b/ffmpeg/libavcodec/msrle.c @@ -0,0 +1,164 @@ +/* + * Microsoft RLE video decoder + * Copyright (C) 2003 the ffmpeg project + * + * 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 video decoder by Mike Melanson (melanson@pcisys.net) + * For more information about the MS RLE format, visit: + * http://www.pcisys.net/~melanson/codecs/ + * + * The MS RLE decoder outputs PAL8 colorspace data. + */ + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include "avcodec.h" +#include "internal.h" +#include "msrledec.h" + +typedef struct MsrleContext { + AVCodecContext *avctx; + AVFrame frame; + + GetByteContext gb; + const unsigned char *buf; + int size; + + uint32_t pal[256]; +} MsrleContext; + +static av_cold int msrle_decode_init(AVCodecContext *avctx) +{ + MsrleContext *s = avctx->priv_data; + int i; + + s->avctx = avctx; + + switch (avctx->bits_per_coded_sample) { + case 1: + avctx->pix_fmt = AV_PIX_FMT_MONOWHITE; + break; + case 4: + case 8: + avctx->pix_fmt = AV_PIX_FMT_PAL8; + break; + case 24: + avctx->pix_fmt = AV_PIX_FMT_BGR24; + break; + default: + av_log(avctx, AV_LOG_ERROR, "unsupported bits per sample\n"); + return AVERROR_INVALIDDATA; + } + + avcodec_get_frame_defaults(&s->frame); + + if (avctx->extradata_size >= 4) + for (i = 0; i < FFMIN(avctx->extradata_size, AVPALETTE_SIZE)/4; i++) + s->pal[i] = 0xFFU<<24 | AV_RL32(avctx->extradata+4*i); + + return 0; +} + +static int msrle_decode_frame(AVCodecContext *avctx, + void *data, int *got_frame, + AVPacket *avpkt) +{ + const uint8_t *buf = avpkt->data; + int buf_size = avpkt->size; + MsrleContext *s = avctx->priv_data; + int istride = FFALIGN(avctx->width*avctx->bits_per_coded_sample, 32) / 8; + int ret; + + s->buf = buf; + s->size = buf_size; + + if ((ret = ff_reget_buffer(avctx, &s->frame)) < 0) + return ret; + + if (avctx->bits_per_coded_sample > 1 && avctx->bits_per_coded_sample <= 8) { + const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, NULL); + + if (pal) { + s->frame.palette_has_changed = 1; + memcpy(s->pal, pal, AVPALETTE_SIZE); + } + /* make the palette available */ + memcpy(s->frame.data[1], s->pal, AVPALETTE_SIZE); + } + + /* FIXME how to correctly detect RLE ??? */ + if (avctx->height * istride == avpkt->size) { /* assume uncompressed */ + int linesize = (avctx->width * avctx->bits_per_coded_sample + 7) / 8; + uint8_t *ptr = s->frame.data[0]; + uint8_t *buf = avpkt->data + (avctx->height-1)*istride; + int i, j; + + for (i = 0; i < avctx->height; i++) { + if (avctx->bits_per_coded_sample == 4) { + for (j = 0; j < avctx->width - 1; j += 2) { + ptr[j+0] = buf[j>>1] >> 4; + ptr[j+1] = buf[j>>1] & 0xF; + } + if (avctx->width & 1) + ptr[j+0] = buf[j>>1] >> 4; + } else { + memcpy(ptr, buf, linesize); + } + buf -= istride; + ptr += s->frame.linesize[0]; + } + } else { + bytestream2_init(&s->gb, buf, buf_size); + ff_msrle_decode(avctx, (AVPicture*)&s->frame, avctx->bits_per_coded_sample, &s->gb); + } + + if ((ret = av_frame_ref(data, &s->frame)) < 0) + return ret; + + *got_frame = 1; + + /* report that the buffer was completely consumed */ + return buf_size; +} + +static av_cold int msrle_decode_end(AVCodecContext *avctx) +{ + MsrleContext *s = avctx->priv_data; + + /* release the last frame */ + av_frame_unref(&s->frame); + + return 0; +} + +AVCodec ff_msrle_decoder = { + .name = "msrle", + .type = AVMEDIA_TYPE_VIDEO, + .id = AV_CODEC_ID_MSRLE, + .priv_data_size = sizeof(MsrleContext), + .init = msrle_decode_init, + .close = msrle_decode_end, + .decode = msrle_decode_frame, + .capabilities = CODEC_CAP_DR1, + .long_name = NULL_IF_CONFIG_SMALL("Microsoft RLE"), +}; |