2 * Tiertex Limited SEQ Video Decoder
3 * Copyright (c) 2006 Gregory Montoir (cyx@users.sourceforge.net)
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 * Tiertex Limited SEQ video decoder
28 #define ALT_BITSTREAM_READER_LE
32 typedef struct SeqVideoContext {
33 AVCodecContext *avctx;
38 static const unsigned char *seq_unpack_rle_block(const unsigned char *src, unsigned char *dst, int dst_size)
44 /* get the rle codes (at most 64 bytes) */
45 init_get_bits(&gb, src, 64 * 8);
46 for (i = 0, sz = 0; i < 64 && sz < dst_size; i++) {
47 code_table[i] = get_sbits(&gb, 4);
48 sz += FFABS(code_table[i]);
50 src += (get_bits_count(&gb) + 7) / 8;
52 /* do the rle unpacking */
53 for (i = 0; i < 64 && dst_size > 0; i++) {
57 memset(dst, *src++, FFMIN(len, dst_size));
59 memcpy(dst, src, FFMIN(len, dst_size));
68 static const unsigned char *seq_decode_op1(SeqVideoContext *seq, const unsigned char *src, unsigned char *dst)
70 const unsigned char *color_table;
73 unsigned char block[8 * 8];
79 src = seq_unpack_rle_block(src, block, sizeof(block));
80 for (b = 0; b < 8; b++) {
81 memcpy(dst, &block[b * 8], 8);
82 dst += seq->frame.linesize[0];
86 src = seq_unpack_rle_block(src, block, sizeof(block));
87 for (i = 0; i < 8; i++) {
88 for (b = 0; b < 8; b++)
89 dst[b * seq->frame.linesize[0]] = block[i * 8 + b];
97 bits = ff_log2_tab[len - 1] + 1;
98 init_get_bits(&gb, src, bits * 8 * 8); src += bits * 8;
99 for (b = 0; b < 8; b++) {
100 for (i = 0; i < 8; i++)
101 dst[i] = color_table[get_bits(&gb, bits)];
102 dst += seq->frame.linesize[0];
109 static const unsigned char *seq_decode_op2(SeqVideoContext *seq, const unsigned char *src, unsigned char *dst)
113 for (i = 0; i < 8; i++) {
116 dst += seq->frame.linesize[0];
122 static const unsigned char *seq_decode_op3(SeqVideoContext *seq, const unsigned char *src, unsigned char *dst)
128 offset = ((pos >> 3) & 7) * seq->frame.linesize[0] + (pos & 7);
129 dst[offset] = *src++;
130 } while (!(pos & 0x80));
135 static void seqvideo_decode(SeqVideoContext *seq, const unsigned char *data, int data_size)
138 int flags, i, j, x, y, op;
146 palette = (uint32_t *)seq->frame.data[1];
147 for (i = 0; i < 256; i++) {
148 for (j = 0; j < 3; j++, data++)
149 c[j] = (*data << 2) | (*data >> 4);
150 palette[i] = AV_RB24(c);
152 seq->frame.palette_has_changed = 1;
156 init_get_bits(&gb, data, 128 * 8); data += 128;
157 for (y = 0; y < 128; y += 8)
158 for (x = 0; x < 256; x += 8) {
159 dst = &seq->frame.data[0][y * seq->frame.linesize[0] + x];
160 op = get_bits(&gb, 2);
163 data = seq_decode_op1(seq, data, dst);
166 data = seq_decode_op2(seq, data, dst);
169 data = seq_decode_op3(seq, data, dst);
176 static av_cold int seqvideo_decode_init(AVCodecContext *avctx)
178 SeqVideoContext *seq = avctx->priv_data;
181 avctx->pix_fmt = PIX_FMT_PAL8;
183 avcodec_get_frame_defaults(&seq->frame);
184 seq->frame.data[0] = NULL;
189 static int seqvideo_decode_frame(AVCodecContext *avctx,
190 void *data, int *data_size,
193 const uint8_t *buf = avpkt->data;
194 int buf_size = avpkt->size;
196 SeqVideoContext *seq = avctx->priv_data;
198 seq->frame.reference = 1;
199 seq->frame.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;
200 if (avctx->reget_buffer(avctx, &seq->frame)) {
201 av_log(seq->avctx, AV_LOG_ERROR, "tiertexseqvideo: reget_buffer() failed\n");
205 seqvideo_decode(seq, buf, buf_size);
207 *data_size = sizeof(AVFrame);
208 *(AVFrame *)data = seq->frame;
213 static av_cold int seqvideo_decode_end(AVCodecContext *avctx)
215 SeqVideoContext *seq = avctx->priv_data;
217 if (seq->frame.data[0])
218 avctx->release_buffer(avctx, &seq->frame);
223 AVCodec ff_tiertexseqvideo_decoder = {
226 CODEC_ID_TIERTEXSEQVIDEO,
227 sizeof(SeqVideoContext),
228 seqvideo_decode_init,
231 seqvideo_decode_frame,
233 .long_name = NULL_IF_CONFIG_SMALL("Tiertex Limited SEQ video"),