1/*
2 * Bitmap Brothers JV video decoder
3 * Copyright (c) 2011 Peter Ross <pross@xvid.org>
4 *
5 * This file is part of Libav.
6 *
7 * Libav 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 * Libav 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 Libav; 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 * Bitmap Brothers JV video decoder
25 * @author Peter Ross <pross@xvid.org>
26 */
27
28#include "avcodec.h"
29#include "dsputil.h"
30#include "get_bits.h"
31#include "libavutil/intreadwrite.h"
32
33typedef struct JvContext {
34    DSPContext dsp;
35    AVFrame    frame;
36    uint32_t   palette[AVPALETTE_COUNT];
37    int        palette_has_changed;
38} JvContext;
39
40static av_cold int decode_init(AVCodecContext *avctx)
41{
42    JvContext *s = avctx->priv_data;
43    avctx->pix_fmt = PIX_FMT_PAL8;
44    dsputil_init(&s->dsp, avctx);
45    return 0;
46}
47
48/**
49 * Decode 2x2 block
50 */
51static inline void decode2x2(GetBitContext *gb, uint8_t *dst, int linesize)
52{
53    int i, j, v[2];
54
55    switch (get_bits(gb, 2)) {
56    case 1:
57        v[0] = get_bits(gb, 8);
58        for (j = 0; j < 2; j++)
59            memset(dst + j*linesize, v[0], 2);
60        break;
61    case 2:
62        v[0] = get_bits(gb, 8);
63        v[1] = get_bits(gb, 8);
64        for (j = 0; j < 2; j++)
65            for (i = 0; i < 2; i++)
66                dst[j*linesize + i] = v[get_bits1(gb)];
67        break;
68    case 3:
69        for (j = 0; j < 2; j++)
70            for (i = 0; i < 2; i++)
71                dst[j*linesize + i] = get_bits(gb, 8);
72    }
73}
74
75/**
76 * Decode 4x4 block
77 */
78static inline void decode4x4(GetBitContext *gb, uint8_t *dst, int linesize)
79{
80    int i, j, v[2];
81
82    switch (get_bits(gb, 2)) {
83    case 1:
84        v[0] = get_bits(gb, 8);
85        for (j = 0; j < 4; j++)
86            memset(dst + j*linesize, v[0], 4);
87        break;
88    case 2:
89        v[0] = get_bits(gb, 8);
90        v[1] = get_bits(gb, 8);
91        for (j = 2; j >= 0; j -= 2) {
92            for (i = 0; i < 4; i++)
93                dst[j*linesize + i]     = v[get_bits1(gb)];
94            for (i = 0; i < 4; i++)
95                dst[(j+1)*linesize + i] = v[get_bits1(gb)];
96        }
97        break;
98    case 3:
99        for (j = 0; j < 4; j += 2)
100            for (i = 0; i < 4; i += 2)
101                decode2x2(gb, dst + j*linesize + i, linesize);
102    }
103}
104
105/**
106 * Decode 8x8 block
107 */
108static inline void decode8x8(GetBitContext *gb, uint8_t *dst, int linesize, DSPContext *dsp)
109{
110    int i, j, v[2];
111
112    switch (get_bits(gb, 2)) {
113    case 1:
114        v[0] = get_bits(gb, 8);
115        dsp->fill_block_tab[1](dst, v[0], linesize, 8);
116        break;
117    case 2:
118        v[0] = get_bits(gb, 8);
119        v[1] = get_bits(gb, 8);
120        for (j = 7; j >= 0; j--)
121            for (i = 0; i <  8; i++)
122                dst[j*linesize + i] = v[get_bits1(gb)];
123        break;
124    case 3:
125        for (j = 0; j < 8; j += 4)
126            for (i = 0; i < 8; i += 4)
127                decode4x4(gb, dst + j*linesize + i, linesize);
128    }
129}
130
131static int decode_frame(AVCodecContext *avctx,
132                        void *data, int *data_size,
133                        AVPacket *avpkt)
134{
135    JvContext *s           = avctx->priv_data;
136    int buf_size           = avpkt->size;
137    const uint8_t *buf     = avpkt->data;
138    const uint8_t *buf_end = buf + buf_size;
139    int video_size, video_type, i, j;
140
141    video_size = AV_RL32(buf);
142    video_type = buf[4];
143    buf += 5;
144
145    if (video_size) {
146        if (avctx->reget_buffer(avctx, &s->frame) < 0) {
147            av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
148            return -1;
149        }
150
151        if (video_type == 0 || video_type == 1) {
152            GetBitContext gb;
153            init_get_bits(&gb, buf, 8 * FFMIN(video_size, buf_end - buf));
154
155            for (j = 0; j < avctx->height; j += 8)
156                for (i = 0; i < avctx->width; i += 8)
157                    decode8x8(&gb, s->frame.data[0] + j*s->frame.linesize[0] + i,
158                              s->frame.linesize[0], &s->dsp);
159
160            buf += video_size;
161        } else if (video_type == 2) {
162            if (buf + 1 <= buf_end) {
163                int v = *buf++;
164                for (j = 0; j < avctx->height; j++)
165                    memset(s->frame.data[0] + j*s->frame.linesize[0], v, avctx->width);
166            }
167        } else {
168            av_log(avctx, AV_LOG_WARNING, "unsupported frame type %i\n", video_type);
169            return AVERROR_INVALIDDATA;
170        }
171    }
172
173    if (buf < buf_end) {
174        for (i = 0; i < AVPALETTE_COUNT && buf + 3 <= buf_end; i++) {
175            s->palette[i] = AV_RB24(buf) << 2;
176            buf += 3;
177        }
178        s->palette_has_changed = 1;
179    }
180
181    if (video_size) {
182        s->frame.key_frame           = 1;
183        s->frame.pict_type           = AV_PICTURE_TYPE_I;
184        s->frame.palette_has_changed = s->palette_has_changed;
185        s->palette_has_changed       = 0;
186        memcpy(s->frame.data[1], s->palette, AVPALETTE_SIZE);
187
188        *data_size      = sizeof(AVFrame);
189        *(AVFrame*)data = s->frame;
190    }
191
192    return buf_size;
193}
194
195static av_cold int decode_close(AVCodecContext *avctx)
196{
197    JvContext *s = avctx->priv_data;
198
199    if(s->frame.data[0])
200        avctx->release_buffer(avctx, &s->frame);
201
202    return 0;
203}
204
205AVCodec ff_jv_decoder = {
206    .name           = "jv",
207    .long_name      = NULL_IF_CONFIG_SMALL("Bitmap Brothers JV video"),
208    .type           = AVMEDIA_TYPE_VIDEO,
209    .id             = CODEC_ID_JV,
210    .priv_data_size = sizeof(JvContext),
211    .init           = decode_init,
212    .close          = decode_close,
213    .decode         = decode_frame,
214    .capabilities   = CODEC_CAP_DR1,
215};
216