1/*
2 * Miro VideoXL codec
3 * Copyright (c) 2004 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 libavcodec/xl.c
24 * Miro VideoXL codec.
25 */
26
27#include "libavutil/intreadwrite.h"
28#include "avcodec.h"
29
30typedef struct VideoXLContext{
31    AVCodecContext *avctx;
32    AVFrame pic;
33} VideoXLContext;
34
35static const int xl_table[32] = {
36   0,   1,   2,   3,   4,   5,   6,   7,
37   8,   9,  12,  15,  20,  25,  34,  46,
38  64,  82,  94, 103, 108, 113, 116, 119,
39 120, 121, 122, 123, 124, 125, 126, 127};
40
41static int decode_frame(AVCodecContext *avctx,
42                        void *data, int *data_size,
43                        const uint8_t *buf, int buf_size)
44{
45    VideoXLContext * const a = avctx->priv_data;
46    AVFrame * const p= (AVFrame*)&a->pic;
47    uint8_t *Y, *U, *V;
48    int i, j;
49    int stride;
50    uint32_t val;
51    int y0, y1, y2, y3 = 0, c0 = 0, c1 = 0;
52
53    if(p->data[0])
54        avctx->release_buffer(avctx, p);
55
56    p->reference = 0;
57    if(avctx->get_buffer(avctx, p) < 0){
58        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
59        return -1;
60    }
61    p->pict_type= FF_I_TYPE;
62    p->key_frame= 1;
63
64    Y = a->pic.data[0];
65    U = a->pic.data[1];
66    V = a->pic.data[2];
67
68    stride = avctx->width - 4;
69    for (i = 0; i < avctx->height; i++) {
70        /* lines are stored in reversed order */
71        buf += stride;
72
73        for (j = 0; j < avctx->width; j += 4) {
74            /* value is stored in LE dword with word swapped */
75            val = AV_RL32(buf);
76            buf -= 4;
77            val = ((val >> 16) & 0xFFFF) | ((val & 0xFFFF) << 16);
78
79            if(!j)
80                y0 = (val & 0x1F) << 2;
81            else
82                y0 = y3 + xl_table[val & 0x1F];
83            val >>= 5;
84            y1 = y0 + xl_table[val & 0x1F];
85            val >>= 5;
86            y2 = y1 + xl_table[val & 0x1F];
87            val >>= 6; /* align to word */
88            y3 = y2 + xl_table[val & 0x1F];
89            val >>= 5;
90            if(!j)
91                c0 = (val & 0x1F) << 2;
92            else
93                c0 += xl_table[val & 0x1F];
94            val >>= 5;
95            if(!j)
96                c1 = (val & 0x1F) << 2;
97            else
98                c1 += xl_table[val & 0x1F];
99
100            Y[j + 0] = y0 << 1;
101            Y[j + 1] = y1 << 1;
102            Y[j + 2] = y2 << 1;
103            Y[j + 3] = y3 << 1;
104
105            U[j >> 2] = c0 << 1;
106            V[j >> 2] = c1 << 1;
107        }
108
109        buf += avctx->width + 4;
110        Y += a->pic.linesize[0];
111        U += a->pic.linesize[1];
112        V += a->pic.linesize[2];
113    }
114
115    *data_size = sizeof(AVFrame);
116    *(AVFrame*)data = a->pic;
117
118    return buf_size;
119}
120
121static av_cold int decode_init(AVCodecContext *avctx){
122//    VideoXLContext * const a = avctx->priv_data;
123
124    avctx->pix_fmt= PIX_FMT_YUV411P;
125
126    return 0;
127}
128
129AVCodec xl_decoder = {
130    "xl",
131    CODEC_TYPE_VIDEO,
132    CODEC_ID_VIXL,
133    sizeof(VideoXLContext),
134    decode_init,
135    NULL,
136    NULL,
137    decode_frame,
138    CODEC_CAP_DR1,
139    .long_name = NULL_IF_CONFIG_SMALL("Miro VideoXL"),
140};
141