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
24 * Miro VideoXL codec.
25 */
26
27 #include "libavutil/common.h"
28 #include "libavutil/intreadwrite.h"
29 #include "avcodec.h"
30 #include "codec_internal.h"
31 #include "internal.h"
32
33 static const int xl_table[32] = {
34 0, 1, 2, 3, 4, 5, 6, 7,
35 8, 9, 12, 15, 20, 25, 34, 46,
36 64, 82, 94, 103, 108, 113, 116, 119,
37 120, 121, 122, 123, 124, 125, 126, 127
38 };
39
decode_frame(AVCodecContext *avctx, AVFrame *p, int *got_frame, AVPacket *avpkt)40 static int decode_frame(AVCodecContext *avctx, AVFrame *p,
41 int *got_frame, AVPacket *avpkt)
42 {
43 const uint8_t *buf = avpkt->data;
44 int buf_size = avpkt->size;
45 uint8_t *Y, *U, *V;
46 int i, j, ret;
47 int stride;
48 uint32_t val;
49 int y0, y1, y2, y3 = 0, c0 = 0, c1 = 0;
50
51 if (avctx->width % 4) {
52 av_log(avctx, AV_LOG_ERROR, "width is not a multiple of 4\n");
53 return AVERROR_INVALIDDATA;
54 }
55 if (buf_size < avctx->width * avctx->height) {
56 av_log(avctx, AV_LOG_ERROR, "Packet is too small\n");
57 return AVERROR_INVALIDDATA;
58 }
59
60 if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
61 return ret;
62 p->pict_type = AV_PICTURE_TYPE_I;
63 p->key_frame = 1;
64
65 Y = p->data[0];
66 U = p->data[1];
67 V = p->data[2];
68
69 stride = avctx->width - 4;
70
71 for (i = 0; i < avctx->height; i++) {
72 /* lines are stored in reversed order */
73 buf += stride;
74
75 for (j = 0; j < avctx->width; j += 4) {
76 /* value is stored in LE dword with word swapped */
77 val = AV_RL32(buf);
78 buf -= 4;
79 val = ((val >> 16) & 0xFFFF) | ((val & 0xFFFF) << 16);
80
81 if (!j)
82 y0 = (val & 0x1F) << 2;
83 else
84 y0 = y3 + xl_table[val & 0x1F];
85 val >>= 5;
86 y1 = y0 + xl_table[val & 0x1F];
87 val >>= 5;
88 y2 = y1 + xl_table[val & 0x1F];
89 val >>= 6; /* align to word */
90 y3 = y2 + xl_table[val & 0x1F];
91 val >>= 5;
92 if (!j)
93 c0 = (val & 0x1F) << 2;
94 else
95 c0 += xl_table[val & 0x1F];
96 val >>= 5;
97 if (!j)
98 c1 = (val & 0x1F) << 2;
99 else
100 c1 += xl_table[val & 0x1F];
101
102 Y[j + 0] = y0 << 1;
103 Y[j + 1] = y1 << 1;
104 Y[j + 2] = y2 << 1;
105 Y[j + 3] = y3 << 1;
106
107 U[j >> 2] = c0 << 1;
108 V[j >> 2] = c1 << 1;
109 }
110
111 buf += avctx->width + 4;
112 Y += p->linesize[0];
113 U += p->linesize[1];
114 V += p->linesize[2];
115 }
116
117 *got_frame = 1;
118
119 return buf_size;
120 }
121
decode_init(AVCodecContext *avctx)122 static av_cold int decode_init(AVCodecContext *avctx)
123 {
124 avctx->pix_fmt = AV_PIX_FMT_YUV411P;
125
126 return 0;
127 }
128
129 const FFCodec ff_xl_decoder = {
130 .p.name = "xl",
131 .p.long_name = NULL_IF_CONFIG_SMALL("Miro VideoXL"),
132 .p.type = AVMEDIA_TYPE_VIDEO,
133 .p.id = AV_CODEC_ID_VIXL,
134 .init = decode_init,
135 FF_CODEC_DECODE_CB(decode_frame),
136 .p.capabilities = AV_CODEC_CAP_DR1,
137 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
138 };
139