Indeo 2 decoder by (Kostya <> kostya.shishkov gmail com)
[libav.git] / libavcodec / indeo2.c
CommitLineData
856dbbff
MN
1/*
2 * Indel Indeo 2 codec
3 * Copyright (c) 2005 Konstantin Shishkov
4 *
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.
9 *
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.
14 *
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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 *
19 */
20
21/**
22 * @file indeo2.c
23 * Intel Indeo 2 decoder.
24 */
25
26#include "avcodec.h"
27#include "bitstream.h"
28#include "indeo2data.h"
29
30typedef struct Ir2Context{
31 AVCodecContext *avctx;
32 AVFrame picture;
33 GetBitContext gb;
34 int decode_delta;
35} Ir2Context;
36
37#define CODE_VLC_BITS 14
38static VLC ir2_vlc;
39
40/* Indeo 2 codes are in range 0x01..0x7F and 0x81..0x90 */
41static inline int ir2_get_code(GetBitContext *gb)
42{
43 int code;
44
45 code = get_vlc2(gb, ir2_vlc.table, CODE_VLC_BITS, 1) + 1;
46 if (code >= 0x80)
47 return (code + 1);
48 return code;
49}
50#define CLAMP_TO_BYTE(value) \
51if (value > 255) \
52 value = 255; \
53else if (value < 0) \
54 value = 0; \
55
56static void ir2_decode_plane(Ir2Context *ctx, int width, int height, uint8_t *dst, int stride,
57 const uint8_t *table)
58{
59 int i;
60 int j;
61 int out = 0;
62 int c;
63 int t;
64
65 /* first line contain absolute values, other lines contain deltas */
66 while (out < width){
67 c = ir2_get_code(&ctx->gb);
68 if(c > 0x80) { /* we have a run */
69 c -= 0x80;
70 for (i = 0; i < c * 2; i++)
71 dst[out++] = 0x80;
72 } else { /* copy two values from table */
73 dst[out++] = table[c * 2];
74 dst[out++] = table[(c * 2) + 1];
75 }
76 }
77 dst += stride;
78
79 for (j = 1; j < height; j++){
80 out = 0;
81 while (out < width){
82 c = ir2_get_code(&ctx->gb);
83 if(c > 0x80) { /* we have a skip */
84 c -= 0x80;
85 for (i = 0; i < c * 2; i++) {
86 dst[out] = dst[out - stride];
87 out++;
88 }
89 } else { /* add two deltas from table */
90 t = dst[out - stride] + (table[c * 2] - 128);
91 CLAMP_TO_BYTE(t);
92 dst[out] = t;
93 out++;
94 t = dst[out - stride] + (table[(c * 2) + 1] - 128);
95 CLAMP_TO_BYTE(t);
96 dst[out] = t;
97 out++;
98 }
99 }
100 dst += stride;
101 }
102}
103
104static void ir2_decode_plane_inter(Ir2Context *ctx, int width, int height, uint8_t *dst, int stride,
105 const uint8_t *table)
106{
107 int j;
108 int out = 0;
109 int c;
110 int t;
111
112 for (j = 0; j < height; j++){
113 out = 0;
114 while (out < width){
115 c = ir2_get_code(&ctx->gb);
116 if(c > 0x80) { /* we have a skip */
117 c -= 0x80;
118 out += c * 2;
119 } else { /* add two deltas from table */
120 t = dst[out] + (table[c * 2] - 128);
121 CLAMP_TO_BYTE(t);
122 dst[out] = t;
123 out++;
124 t = dst[out] + (table[(c * 2) + 1] - 128);
125 CLAMP_TO_BYTE(t);
126 dst[out] = t;
127 out++;
128 }
129 }
130 dst += stride;
131 }
132}
133
134static int ir2_decode_frame(AVCodecContext *avctx,
135 void *data, int *data_size,
136 uint8_t *buf, int buf_size)
137{
138 Ir2Context * const s = avctx->priv_data;
139 AVFrame *picture = data;
140 AVFrame * const p= (AVFrame*)&s->picture;
141 int start;
142 int i;
143
144 if(p->data[0])
145 avctx->release_buffer(avctx, p);
146
147 p->reference = 1;
148 p->buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;
149 if (avctx->reget_buffer(avctx, p)) {
150 av_log(s->avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
151 return -1;
152 }
153
154 s->decode_delta = buf[18];
155
156 /* decide whether frame uses deltas or not */
157
158 for (i = 0; i < buf_size; i++)
159 buf[i] = ff_reverse[buf[i]];
160
161 start = 48; /* hardcoded for now */
162
163 init_get_bits(&s->gb, buf + start, buf_size - start);
164
165 if (s->decode_delta) { /* intraframe */
166 ir2_decode_plane(s, avctx->width, avctx->height,
167 s->picture.data[0], s->picture.linesize[0], ir2_luma_table);
168 /* swapped U and V */
169 ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2,
170 s->picture.data[2], s->picture.linesize[2], ir2_luma_table);
171 ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2,
172 s->picture.data[1], s->picture.linesize[1], ir2_luma_table);
173 } else { /* interframe */
174 ir2_decode_plane_inter(s, avctx->width, avctx->height,
175 s->picture.data[0], s->picture.linesize[0], ir2_luma_table);
176 /* swapped U and V */
177 ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2,
178 s->picture.data[2], s->picture.linesize[2], ir2_luma_table);
179 ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2,
180 s->picture.data[1], s->picture.linesize[1], ir2_luma_table);
181 }
182
183 *picture= *(AVFrame*)&s->picture;
184 *data_size = sizeof(AVPicture);
185
186 return buf_size;
187}
188
189static int ir2_decode_init(AVCodecContext *avctx){
190 Ir2Context * const ic = avctx->priv_data;
191
192 ic->avctx = avctx;
193
194 avctx->pix_fmt= PIX_FMT_YUV410P;
195
196 if (!ir2_vlc.table)
197 init_vlc(&ir2_vlc, CODE_VLC_BITS, IR2_CODES,
198 &ir2_codes[0][1], 4, 2,
199 &ir2_codes[0][0], 4, 2, 1);
200
201 return 0;
202}
203
204AVCodec indeo2_decoder = {
205 "indeo2",
206 CODEC_TYPE_VIDEO,
207 CODEC_ID_INDEO2,
208 sizeof(Ir2Context),
209 ir2_decode_init,
210 NULL,
211 NULL,
212 ir2_decode_frame,
213 CODEC_CAP_DR1,
214};