3 * Copyright (c) 2005 Konstantin Shishkov
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 * Intel Indeo 2 decoder.
25 #define ALT_BITSTREAM_READER_LE
27 #include "bitstream.h"
28 #include "indeo2data.h"
30 typedef struct Ir2Context{
31 AVCodecContext *avctx;
37 #define CODE_VLC_BITS 14
40 /* Indeo 2 codes are in range 0x01..0x7F and 0x81..0x90 */
41 static inline int ir2_get_code(GetBitContext *gb)
43 return get_vlc2(gb, ir2_vlc.table, CODE_VLC_BITS, 1) + 1;
46 static int ir2_decode_plane(Ir2Context *ctx, int width, int height, uint8_t *dst, int stride,
58 /* first line contain absolute values, other lines contain deltas */
60 c = ir2_get_code(&ctx->gb);
61 if(c >= 0x80) { /* we have a run */
65 for (i = 0; i < c * 2; i++)
67 } else { /* copy two values from table */
68 dst[out++] = table[c * 2];
69 dst[out++] = table[(c * 2) + 1];
74 for (j = 1; j < height; j++){
77 c = ir2_get_code(&ctx->gb);
78 if(c >= 0x80) { /* we have a skip */
82 for (i = 0; i < c * 2; i++) {
83 dst[out] = dst[out - stride];
86 } else { /* add two deltas from table */
87 t = dst[out - stride] + (table[c * 2] - 128);
91 t = dst[out - stride] + (table[(c * 2) + 1] - 128);
102 static int ir2_decode_plane_inter(Ir2Context *ctx, int width, int height, uint8_t *dst, int stride,
103 const uint8_t *table)
113 for (j = 0; j < height; j++){
116 c = ir2_get_code(&ctx->gb);
117 if(c >= 0x80) { /* we have a skip */
120 } else { /* add two deltas from table */
121 t = dst[out] + (((table[c * 2] - 128)*3) >> 2);
125 t = dst[out] + (((table[(c * 2) + 1] - 128)*3) >> 2);
136 static int ir2_decode_frame(AVCodecContext *avctx,
137 void *data, int *data_size,
138 uint8_t *buf, int buf_size)
140 Ir2Context * const s = avctx->priv_data;
141 AVFrame *picture = data;
142 AVFrame * const p= (AVFrame*)&s->picture;
146 avctx->release_buffer(avctx, p);
149 p->buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;
150 if (avctx->reget_buffer(avctx, p)) {
151 av_log(s->avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
155 s->decode_delta = buf[18];
157 /* decide whether frame uses deltas or not */
158 #ifndef ALT_BITSTREAM_READER_LE
159 for (i = 0; i < buf_size; i++)
160 buf[i] = ff_reverse[buf[i]];
162 start = 48; /* hardcoded for now */
164 init_get_bits(&s->gb, buf + start, buf_size - start);
166 if (s->decode_delta) { /* intraframe */
167 ir2_decode_plane(s, avctx->width, avctx->height,
168 s->picture.data[0], s->picture.linesize[0], ir2_luma_table);
169 /* swapped U and V */
170 ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2,
171 s->picture.data[2], s->picture.linesize[2], ir2_luma_table);
172 ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2,
173 s->picture.data[1], s->picture.linesize[1], ir2_luma_table);
174 } else { /* interframe */
175 ir2_decode_plane_inter(s, avctx->width, avctx->height,
176 s->picture.data[0], s->picture.linesize[0], ir2_luma_table);
177 /* swapped U and V */
178 ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2,
179 s->picture.data[2], s->picture.linesize[2], ir2_luma_table);
180 ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2,
181 s->picture.data[1], s->picture.linesize[1], ir2_luma_table);
184 *picture= *(AVFrame*)&s->picture;
185 *data_size = sizeof(AVPicture);
190 static int ir2_decode_init(AVCodecContext *avctx){
191 Ir2Context * const ic = avctx->priv_data;
195 avctx->pix_fmt= PIX_FMT_YUV410P;
198 init_vlc(&ir2_vlc, CODE_VLC_BITS, IR2_CODES,
199 &ir2_codes[0][1], 4, 2,
200 #ifdef ALT_BITSTREAM_READER_LE
201 &ir2_codes[0][0], 4, 2, INIT_VLC_USE_STATIC | INIT_VLC_LE);
203 &ir2_codes[0][0], 4, 2, INIT_VLC_USE_STATIC);
209 AVCodec indeo2_decoder = {