2 * Bethesda VID video decoder
3 * Copyright (C) 2007 Nicholas Tung
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 * @brief Bethesda Softworks VID Video Decoder
25 * @author Nicholas Tung [ntung (at. ntung com] (2007-03)
26 * @see http://wiki.multimedia.cx/index.php?title=Bethsoft_VID
27 * @see http://www.svatopluk.com/andux/docs/dfvid.html
30 #include "libavutil/common.h"
32 #include "bethsoftvideo.h"
33 #include "bytestream.h"
35 typedef struct BethsoftvidContext {
39 static av_cold int bethsoftvid_decode_init(AVCodecContext *avctx)
41 BethsoftvidContext *vid = avctx->priv_data;
42 avcodec_get_frame_defaults(&vid->frame);
43 vid->frame.reference = 3;
44 vid->frame.buffer_hints = FF_BUFFER_HINTS_VALID |
45 FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;
46 avctx->pix_fmt = PIX_FMT_PAL8;
50 static void set_palette(AVFrame * frame, const uint8_t * palette_buffer)
52 uint32_t * palette = (uint32_t *)frame->data[1];
54 for(a = 0; a < 256; a++){
55 palette[a] = 0xFF << 24 | AV_RB24(&palette_buffer[a * 3]) * 4;
56 palette[a] |= palette[a] >> 6 & 0x30303;
58 frame->palette_has_changed = 1;
61 static int bethsoftvid_decode_frame(AVCodecContext *avctx,
62 void *data, int *data_size,
65 const uint8_t *buf = avpkt->data;
66 int buf_size = avpkt->size;
67 BethsoftvidContext * vid = avctx->priv_data;
71 int remaining = avctx->width; // number of bytes remaining on a line
72 const int wrap_to_next_line = vid->frame.linesize[0] - avctx->width;
76 if (avctx->reget_buffer(avctx, &vid->frame)) {
77 av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
80 dst = vid->frame.data[0];
81 frame_end = vid->frame.data[0] + vid->frame.linesize[0] * avctx->height;
83 switch(block_type = *buf++){
85 set_palette(&vid->frame, buf);
87 case VIDEO_YOFF_P_FRAME:
88 yoffset = bytestream_get_le16(&buf);
89 if(yoffset >= avctx->height)
91 dst += vid->frame.linesize[0] * yoffset;
95 while((code = *buf++)){
96 int length = code & 0x7f;
98 // copy any bytes starting at the current position, and ending at the frame width
99 while(length > remaining){
101 bytestream_get_buffer(&buf, dst, remaining);
102 else if(block_type == VIDEO_I_FRAME)
103 memset(dst, buf[0], remaining);
104 length -= remaining; // decrement the number of bytes to be copied
105 dst += remaining + wrap_to_next_line; // skip over extra bytes at end of frame
106 remaining = avctx->width;
111 // copy any remaining bytes after / if line overflows
113 bytestream_get_buffer(&buf, dst, length);
114 else if(block_type == VIDEO_I_FRAME)
115 memset(dst, *buf++, length);
121 *data_size = sizeof(AVFrame);
122 *(AVFrame*)data = vid->frame;
127 static av_cold int bethsoftvid_decode_end(AVCodecContext *avctx)
129 BethsoftvidContext * vid = avctx->priv_data;
130 if(vid->frame.data[0])
131 avctx->release_buffer(avctx, &vid->frame);
135 AVCodec ff_bethsoftvid_decoder = {
136 .name = "bethsoftvid",
137 .type = AVMEDIA_TYPE_VIDEO,
138 .id = CODEC_ID_BETHSOFTVID,
139 .priv_data_size = sizeof(BethsoftvidContext),
140 .init = bethsoftvid_decode_init,
141 .close = bethsoftvid_decode_end,
142 .decode = bethsoftvid_decode_frame,
143 .capabilities = CODEC_CAP_DR1,
144 .long_name = NULL_IF_CONFIG_SMALL("Bethesda VID video"),