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#define BITSTREAM_READER_LE
28#include "libavutil/attributes.h"
29#include "avcodec.h"
30#include "get_bits.h"
31#include "indeo2data.h"
32#include "internal.h"
33#include "mathops.h"
34
35typedef struct Ir2Context{
36    AVCodecContext *avctx;
37    AVFrame *picture;
38    GetBitContext gb;
39    int decode_delta;
40} Ir2Context;
41
42#define CODE_VLC_BITS 14
43static VLC ir2_vlc;
44
45/* Indeo 2 codes are in range 0x01..0x7F and 0x81..0x90 */
46static inline int ir2_get_code(GetBitContext *gb)
47{
48    return get_vlc2(gb, ir2_vlc.table, CODE_VLC_BITS, 1) + 1;
49}
50
51static int ir2_decode_plane(Ir2Context *ctx, int width, int height, uint8_t *dst,
52                            int pitch, const uint8_t *table)
53{
54    int i;
55    int j;
56    int out = 0;
57    int c;
58    int t;
59
60    if (width & 1)
61        return AVERROR_INVALIDDATA;
62
63    /* first line contain absolute values, other lines contain deltas */
64    while (out < width) {
65        c = ir2_get_code(&ctx->gb);
66        if (c >= 0x80) { /* we have a run */
67            c -= 0x7F;
68            if (out + c*2 > width)
69                return AVERROR_INVALIDDATA;
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 += pitch;
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 -= 0x7F;
85                if (out + c*2 > width)
86                    return AVERROR_INVALIDDATA;
87                for (i = 0; i < c * 2; i++) {
88                    dst[out] = dst[out - pitch];
89                    out++;
90                }
91            } else { /* add two deltas from table */
92                t        = dst[out - pitch] + (table[c * 2] - 128);
93                t        = av_clip_uint8(t);
94                dst[out] = t;
95                out++;
96                t        = dst[out - pitch] + (table[(c * 2) + 1] - 128);
97                t        = av_clip_uint8(t);
98                dst[out] = t;
99                out++;
100            }
101        }
102        dst += pitch;
103    }
104    return 0;
105}
106
107static int ir2_decode_plane_inter(Ir2Context *ctx, int width, int height, uint8_t *dst,
108                                  int pitch, const uint8_t *table)
109{
110    int j;
111    int out = 0;
112    int c;
113    int t;
114
115    if (width & 1)
116        return AVERROR_INVALIDDATA;
117
118    for (j = 0; j < height; j++) {
119        out = 0;
120        while (out < width) {
121            c = ir2_get_code(&ctx->gb);
122            if (c >= 0x80) { /* we have a skip */
123                c   -= 0x7F;
124                out += c * 2;
125            } else { /* add two deltas from table */
126                t        = dst[out] + (((table[c * 2] - 128)*3) >> 2);
127                t        = av_clip_uint8(t);
128                dst[out] = t;
129                out++;
130                t        = dst[out] + (((table[(c * 2) + 1] - 128)*3) >> 2);
131                t        = av_clip_uint8(t);
132                dst[out] = t;
133                out++;
134            }
135        }
136        dst += pitch;
137    }
138    return 0;
139}
140
141static int ir2_decode_frame(AVCodecContext *avctx,
142                        void *data, int *got_frame,
143                        AVPacket *avpkt)
144{
145    Ir2Context * const s = avctx->priv_data;
146    const uint8_t *buf   = avpkt->data;
147    int buf_size         = avpkt->size;
148    AVFrame *picture     = data;
149    AVFrame * const p    = s->picture;
150    int start, ret;
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    init_get_bits(&s->gb, buf + start, (buf_size - start) * 8);
171
172    if (s->decode_delta) { /* intraframe */
173        if ((ret = ir2_decode_plane(s, avctx->width, avctx->height,
174                                    p->data[0], p->linesize[0],
175                                    ir2_luma_table)) < 0)
176            return ret;
177
178        /* swapped U and V */
179        if ((ret = ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2,
180                                    p->data[2], p->linesize[2],
181                                    ir2_luma_table)) < 0)
182            return ret;
183        if ((ret = ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2,
184                                    p->data[1], p->linesize[1],
185                                    ir2_luma_table)) < 0)
186            return ret;
187    } else { /* interframe */
188        if ((ret = ir2_decode_plane_inter(s, avctx->width, avctx->height,
189                                          p->data[0], p->linesize[0],
190                                          ir2_luma_table)) < 0)
191            return ret;
192        /* swapped U and V */
193        if ((ret = ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2,
194                                          p->data[2], p->linesize[2],
195                                          ir2_luma_table)) < 0)
196            return ret;
197        if ((ret = ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2,
198                                          p->data[1], p->linesize[1],
199                                          ir2_luma_table)) < 0)
200            return ret;
201    }
202
203    if ((ret = av_frame_ref(picture, p)) < 0)
204        return ret;
205
206    *got_frame = 1;
207
208    return buf_size;
209}
210
211static av_cold int ir2_decode_init(AVCodecContext *avctx)
212{
213    Ir2Context * const ic = avctx->priv_data;
214    static VLC_TYPE vlc_tables[1 << CODE_VLC_BITS][2];
215
216    ic->avctx = avctx;
217
218    avctx->pix_fmt= AV_PIX_FMT_YUV410P;
219
220    ic->picture = av_frame_alloc();
221    if (!ic->picture)
222        return AVERROR(ENOMEM);
223
224    ir2_vlc.table = vlc_tables;
225    ir2_vlc.table_allocated = 1 << CODE_VLC_BITS;
226#ifdef BITSTREAM_READER_LE
227        init_vlc(&ir2_vlc, CODE_VLC_BITS, IR2_CODES,
228                 &ir2_codes[0][1], 4, 2,
229                 &ir2_codes[0][0], 4, 2, INIT_VLC_USE_NEW_STATIC | INIT_VLC_LE);
230#else
231        init_vlc(&ir2_vlc, CODE_VLC_BITS, IR2_CODES,
232                 &ir2_codes[0][1], 4, 2,
233                 &ir2_codes[0][0], 4, 2, INIT_VLC_USE_NEW_STATIC);
234#endif
235
236    return 0;
237}
238
239static av_cold int ir2_decode_end(AVCodecContext *avctx)
240{
241    Ir2Context * const ic = avctx->priv_data;
242
243    av_frame_free(&ic->picture);
244
245    return 0;
246}
247
248AVCodec ff_indeo2_decoder = {
249    .name           = "indeo2",
250    .long_name      = NULL_IF_CONFIG_SMALL("Intel Indeo 2"),
251    .type           = AVMEDIA_TYPE_VIDEO,
252    .id             = AV_CODEC_ID_INDEO2,
253    .priv_data_size = sizeof(Ir2Context),
254    .init           = ir2_decode_init,
255    .close          = ir2_decode_end,
256    .decode         = ir2_decode_frame,
257    .capabilities   = CODEC_CAP_DR1,
258};
259