2 * Microsoft RLE video decoder
3 * Copyright (C) 2003 The FFmpeg project
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
24 * MS RLE video decoder by Mike Melanson (melanson@pcisys.net)
25 * For more information about the MS RLE format, visit:
26 * http://www.pcisys.net/~melanson/codecs/
28 * The MS RLE decoder outputs PAL8 colorspace data.
38 #include "libavutil/imgutils.h"
40 typedef struct MsrleContext {
41 AVCodecContext *avctx;
45 const unsigned char *buf;
51 static av_cold int msrle_decode_init(AVCodecContext *avctx)
53 MsrleContext *s = avctx->priv_data;
58 switch (avctx->bits_per_coded_sample) {
60 avctx->pix_fmt = AV_PIX_FMT_MONOWHITE;
64 avctx->pix_fmt = AV_PIX_FMT_PAL8;
67 avctx->pix_fmt = AV_PIX_FMT_BGR24;
70 av_log(avctx, AV_LOG_ERROR, "unsupported bits per sample\n");
71 return AVERROR_INVALIDDATA;
74 s->frame = av_frame_alloc();
76 return AVERROR(ENOMEM);
78 if (avctx->extradata_size >= 4)
79 for (i = 0; i < FFMIN(avctx->extradata_size, AVPALETTE_SIZE)/4; i++)
80 s->pal[i] = 0xFFU<<24 | AV_RL32(avctx->extradata+4*i);
85 static int msrle_decode_frame(AVCodecContext *avctx,
86 void *data, int *got_frame,
89 const uint8_t *buf = avpkt->data;
90 int buf_size = avpkt->size;
91 MsrleContext *s = avctx->priv_data;
92 int istride = FFALIGN(avctx->width*avctx->bits_per_coded_sample, 32) / 8;
98 if (buf_size < 2) //Minimally a end of picture code should be there
99 return AVERROR_INVALIDDATA;
101 if ((ret = ff_reget_buffer(avctx, s->frame)) < 0)
104 if (avctx->bits_per_coded_sample > 1 && avctx->bits_per_coded_sample <= 8) {
106 const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, &size);
108 if (pal && size == AVPALETTE_SIZE) {
109 s->frame->palette_has_changed = 1;
110 memcpy(s->pal, pal, AVPALETTE_SIZE);
112 av_log(avctx, AV_LOG_ERROR, "Palette size %d is wrong\n", size);
114 /* make the palette available */
115 memcpy(s->frame->data[1], s->pal, AVPALETTE_SIZE);
118 /* FIXME how to correctly detect RLE ??? */
119 if (avctx->height * istride == avpkt->size) { /* assume uncompressed */
120 int linesize = av_image_get_linesize(avctx->pix_fmt, avctx->width, 0);
121 uint8_t *ptr = s->frame->data[0];
122 uint8_t *buf = avpkt->data + (avctx->height-1)*istride;
128 for (i = 0; i < avctx->height; i++) {
129 if (avctx->bits_per_coded_sample == 4) {
130 for (j = 0; j < avctx->width - 1; j += 2) {
131 ptr[j+0] = buf[j>>1] >> 4;
132 ptr[j+1] = buf[j>>1] & 0xF;
134 if (avctx->width & 1)
135 ptr[j+0] = buf[j>>1] >> 4;
137 memcpy(ptr, buf, linesize);
140 ptr += s->frame->linesize[0];
143 bytestream2_init(&s->gb, buf, buf_size);
144 ff_msrle_decode(avctx, s->frame, avctx->bits_per_coded_sample, &s->gb);
147 if ((ret = av_frame_ref(data, s->frame)) < 0)
152 /* report that the buffer was completely consumed */
156 static av_cold int msrle_decode_end(AVCodecContext *avctx)
158 MsrleContext *s = avctx->priv_data;
160 /* release the last frame */
161 av_frame_free(&s->frame);
166 AVCodec ff_msrle_decoder = {
168 .long_name = NULL_IF_CONFIG_SMALL("Microsoft RLE"),
169 .type = AVMEDIA_TYPE_VIDEO,
170 .id = AV_CODEC_ID_MSRLE,
171 .priv_data_size = sizeof(MsrleContext),
172 .init = msrle_decode_init,
173 .close = msrle_decode_end,
174 .decode = msrle_decode_frame,
175 .capabilities = AV_CODEC_CAP_DR1,