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path: root/libavcodec/indeo2.c (plain)
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1/*
2 * Intel Indeo 2 codec
3 * Copyright (c) 2005 Konstantin Shishkov
4 *
5 * This file is part of FFmpeg.
6 *
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.
11 *
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.
16 *
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
20 */
21
22/**
23 * @file
24 * Intel Indeo 2 decoder.
25 */
26
27#include "libavutil/attributes.h"
28
29#define BITSTREAM_READER_LE
30#include "avcodec.h"
31#include "get_bits.h"
32#include "indeo2data.h"
33#include "internal.h"
34#include "mathops.h"
35
36typedef struct Ir2Context{
37 AVCodecContext *avctx;
38 AVFrame *picture;
39 GetBitContext gb;
40 int decode_delta;
41} Ir2Context;
42
43#define CODE_VLC_BITS 14
44static VLC ir2_vlc;
45
46/* Indeo 2 codes are in range 0x01..0x7F and 0x81..0x90 */
47static inline int ir2_get_code(GetBitContext *gb)
48{
49 return get_vlc2(gb, ir2_vlc.table, CODE_VLC_BITS, 1) + 1;
50}
51
52static int ir2_decode_plane(Ir2Context *ctx, int width, int height, uint8_t *dst,
53 int pitch, const uint8_t *table)
54{
55 int i;
56 int j;
57 int out = 0;
58
59 if (width & 1)
60 return AVERROR_INVALIDDATA;
61
62 /* first line contain absolute values, other lines contain deltas */
63 while (out < width) {
64 int c = ir2_get_code(&ctx->gb);
65 if (c >= 0x80) { /* we have a run */
66 c -= 0x7F;
67 if (out + c*2 > width)
68 return AVERROR_INVALIDDATA;
69 for (i = 0; i < c * 2; i++)
70 dst[out++] = 0x80;
71 } else { /* copy two values from table */
72 dst[out++] = table[c * 2];
73 dst[out++] = table[(c * 2) + 1];
74 }
75 }
76 dst += pitch;
77
78 for (j = 1; j < height; j++) {
79 out = 0;
80 while (out < width) {
81 int c = ir2_get_code(&ctx->gb);
82 if (c >= 0x80) { /* we have a skip */
83 c -= 0x7F;
84 if (out + c*2 > width)
85 return AVERROR_INVALIDDATA;
86 for (i = 0; i < c * 2; i++) {
87 dst[out] = dst[out - pitch];
88 out++;
89 }
90 } else { /* add two deltas from table */
91 int t = dst[out - pitch] + (table[c * 2] - 128);
92 t = av_clip_uint8(t);
93 dst[out] = t;
94 out++;
95 t = dst[out - pitch] + (table[(c * 2) + 1] - 128);
96 t = av_clip_uint8(t);
97 dst[out] = t;
98 out++;
99 }
100 }
101 dst += pitch;
102 }
103 return 0;
104}
105
106static int ir2_decode_plane_inter(Ir2Context *ctx, int width, int height, uint8_t *dst,
107 int pitch, const uint8_t *table)
108{
109 int j;
110 int out = 0;
111 int c;
112 int t;
113
114 if (width & 1)
115 return AVERROR_INVALIDDATA;
116
117 for (j = 0; j < height; j++) {
118 out = 0;
119 while (out < width) {
120 c = ir2_get_code(&ctx->gb);
121 if (c >= 0x80) { /* we have a skip */
122 c -= 0x7F;
123 out += c * 2;
124 } else { /* add two deltas from table */
125 t = dst[out] + (((table[c * 2] - 128)*3) >> 2);
126 t = av_clip_uint8(t);
127 dst[out] = t;
128 out++;
129 t = dst[out] + (((table[(c * 2) + 1] - 128)*3) >> 2);
130 t = av_clip_uint8(t);
131 dst[out] = t;
132 out++;
133 }
134 }
135 dst += pitch;
136 }
137 return 0;
138}
139
140static int ir2_decode_frame(AVCodecContext *avctx,
141 void *data, int *got_frame,
142 AVPacket *avpkt)
143{
144 Ir2Context * const s = avctx->priv_data;
145 const uint8_t *buf = avpkt->data;
146 int buf_size = avpkt->size;
147 AVFrame *picture = data;
148 AVFrame * const p = s->picture;
149 int start, ret;
150 int ltab, ctab;
151
152 if ((ret = ff_reget_buffer(avctx, p)) < 0)
153 return ret;
154
155 start = 48; /* hardcoded for now */
156
157 if (start >= buf_size) {
158 av_log(s->avctx, AV_LOG_ERROR, "input buffer size too small (%d)\n", buf_size);
159 return AVERROR_INVALIDDATA;
160 }
161
162 s->decode_delta = buf[18];
163
164 /* decide whether frame uses deltas or not */
165#ifndef BITSTREAM_READER_LE
166 for (i = 0; i < buf_size; i++)
167 buf[i] = ff_reverse[buf[i]];
168#endif
169
170 if ((ret = init_get_bits8(&s->gb, buf + start, buf_size - start)) < 0)
171 return ret;
172
173 ltab = buf[0x22] & 3;
174 ctab = buf[0x22] >> 2;
175
176 if (ctab > 3) {
177 av_log(avctx, AV_LOG_ERROR, "ctab %d is invalid\n", ctab);
178 return AVERROR_INVALIDDATA;
179 }
180
181 if (s->decode_delta) { /* intraframe */
182 if ((ret = ir2_decode_plane(s, avctx->width, avctx->height,
183 p->data[0], p->linesize[0],
184 ir2_delta_table[ltab])) < 0)
185 return ret;
186
187 /* swapped U and V */
188 if ((ret = ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2,
189 p->data[2], p->linesize[2],
190 ir2_delta_table[ctab])) < 0)
191 return ret;
192 if ((ret = ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2,
193 p->data[1], p->linesize[1],
194 ir2_delta_table[ctab])) < 0)
195 return ret;
196 } else { /* interframe */
197 if ((ret = ir2_decode_plane_inter(s, avctx->width, avctx->height,
198 p->data[0], p->linesize[0],
199 ir2_delta_table[ltab])) < 0)
200 return ret;
201 /* swapped U and V */
202 if ((ret = ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2,
203 p->data[2], p->linesize[2],
204 ir2_delta_table[ctab])) < 0)
205 return ret;
206 if ((ret = ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2,
207 p->data[1], p->linesize[1],
208 ir2_delta_table[ctab])) < 0)
209 return ret;
210 }
211
212 if ((ret = av_frame_ref(picture, p)) < 0)
213 return ret;
214
215 *got_frame = 1;
216
217 return buf_size;
218}
219
220static av_cold int ir2_decode_init(AVCodecContext *avctx)
221{
222 Ir2Context * const ic = avctx->priv_data;
223 static VLC_TYPE vlc_tables[1 << CODE_VLC_BITS][2];
224
225 ic->avctx = avctx;
226
227 avctx->pix_fmt= AV_PIX_FMT_YUV410P;
228
229 ic->picture = av_frame_alloc();
230 if (!ic->picture)
231 return AVERROR(ENOMEM);
232
233 ir2_vlc.table = vlc_tables;
234 ir2_vlc.table_allocated = 1 << CODE_VLC_BITS;
235#ifdef BITSTREAM_READER_LE
236 init_vlc(&ir2_vlc, CODE_VLC_BITS, IR2_CODES,
237 &ir2_codes[0][1], 4, 2,
238 &ir2_codes[0][0], 4, 2, INIT_VLC_USE_NEW_STATIC | INIT_VLC_LE);
239#else
240 init_vlc(&ir2_vlc, CODE_VLC_BITS, IR2_CODES,
241 &ir2_codes[0][1], 4, 2,
242 &ir2_codes[0][0], 4, 2, INIT_VLC_USE_NEW_STATIC);
243#endif
244
245 return 0;
246}
247
248static av_cold int ir2_decode_end(AVCodecContext *avctx)
249{
250 Ir2Context * const ic = avctx->priv_data;
251
252 av_frame_free(&ic->picture);
253
254 return 0;
255}
256
257AVCodec ff_indeo2_decoder = {
258 .name = "indeo2",
259 .long_name = NULL_IF_CONFIG_SMALL("Intel Indeo 2"),
260 .type = AVMEDIA_TYPE_VIDEO,
261 .id = AV_CODEC_ID_INDEO2,
262 .priv_data_size = sizeof(Ir2Context),
263 .init = ir2_decode_init,
264 .close = ir2_decode_end,
265 .decode = ir2_decode_frame,
266 .capabilities = AV_CODEC_CAP_DR1,
267};
268
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