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"
34 #include "codec_internal.h"
37 typedef struct BethsoftvidContext {
42 static av_cold int bethsoftvid_decode_init(AVCodecContext *avctx)
44 BethsoftvidContext *vid = avctx->priv_data;
45 avctx->pix_fmt = AV_PIX_FMT_PAL8;
47 vid->frame = av_frame_alloc();
49 return AVERROR(ENOMEM);
54 static int set_palette(BethsoftvidContext *ctx, GetByteContext *g)
56 uint32_t *palette = (uint32_t *)ctx->frame->data[1];
59 if (bytestream2_get_bytes_left(g) < 256*3)
60 return AVERROR_INVALIDDATA;
62 for(a = 0; a < 256; a++){
63 palette[a] = 0xFFU << 24 | bytestream2_get_be24u(g) * 4;
64 palette[a] |= palette[a] >> 6 & 0x30303;
66 #if FF_API_PALETTE_HAS_CHANGED
67 FF_DISABLE_DEPRECATION_WARNINGS
68 ctx->frame->palette_has_changed = 1;
69 FF_ENABLE_DEPRECATION_WARNINGS
74 static int bethsoftvid_decode_frame(AVCodecContext *avctx, AVFrame *rframe,
75 int *got_frame, AVPacket *avpkt)
77 BethsoftvidContext * vid = avctx->priv_data;
81 int remaining = avctx->width; // number of bytes remaining on a line
82 int wrap_to_next_line;
86 bytestream2_init(&vid->g, avpkt->data, avpkt->size);
87 block_type = bytestream2_get_byte(&vid->g);
88 if (block_type < 1 || block_type > 4)
89 return AVERROR_INVALIDDATA;
91 if ((ret = ff_reget_buffer(avctx, vid->frame, 0)) < 0)
93 wrap_to_next_line = vid->frame->linesize[0] - avctx->width;
95 if (avpkt->side_data_elems > 0 &&
96 avpkt->side_data[0].type == AV_PKT_DATA_PALETTE) {
98 bytestream2_init(&g, avpkt->side_data[0].data,
99 avpkt->side_data[0].size);
100 if ((ret = set_palette(vid, &g)) < 0)
104 dst = vid->frame->data[0];
105 frame_end = vid->frame->data[0] + vid->frame->linesize[0] * avctx->height;
108 case PALETTE_BLOCK: {
110 if ((ret = set_palette(vid, &vid->g)) < 0) {
111 av_log(avctx, AV_LOG_ERROR, "error reading palette\n");
114 return bytestream2_tell(&vid->g);
116 case VIDEO_YOFF_P_FRAME:
117 yoffset = bytestream2_get_le16(&vid->g);
118 if(yoffset >= avctx->height)
119 return AVERROR_INVALIDDATA;
120 dst += vid->frame->linesize[0] * yoffset;
125 return AVERROR_INVALIDDATA;
129 while((code = bytestream2_get_byte(&vid->g))){
130 int length = code & 0x7f;
132 // copy any bytes starting at the current position, and ending at the frame width
133 while(length > remaining){
135 bytestream2_get_buffer(&vid->g, dst, remaining);
136 else if(block_type == VIDEO_I_FRAME)
137 memset(dst, bytestream2_peek_byte(&vid->g), remaining);
138 length -= remaining; // decrement the number of bytes to be copied
139 dst += remaining + wrap_to_next_line; // skip over extra bytes at end of frame
140 remaining = avctx->width;
145 // copy any remaining bytes after / if line overflows
147 bytestream2_get_buffer(&vid->g, dst, length);
148 else if(block_type == VIDEO_I_FRAME)
149 memset(dst, bytestream2_get_byte(&vid->g), length);
155 if ((ret = av_frame_ref(rframe, vid->frame)) < 0)
163 static av_cold int bethsoftvid_decode_end(AVCodecContext *avctx)
165 BethsoftvidContext * vid = avctx->priv_data;
166 av_frame_free(&vid->frame);
170 const FFCodec ff_bethsoftvid_decoder = {
171 .p.name = "bethsoftvid",
172 CODEC_LONG_NAME("Bethesda VID video"),
173 .p.type = AVMEDIA_TYPE_VIDEO,
174 .p.id = AV_CODEC_ID_BETHSOFTVID,
175 .priv_data_size = sizeof(BethsoftvidContext),
176 .init = bethsoftvid_decode_init,
177 .close = bethsoftvid_decode_end,
178 FF_CODEC_DECODE_CB(bethsoftvid_decode_frame),
179 .p.capabilities = AV_CODEC_CAP_DR1,