ceed13f5b81c621d776ea9c442ee9e8bebf8ac7d
[libav.git] / libavcodec / 8bps.c
1 /*
2 * Quicktime Planar RGB (8BPS) Video Decoder
3 * Copyright (C) 2003 Roberto Togni
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 * QT 8BPS Video Decoder by Roberto Togni
25 * For more information about the 8BPS format, visit:
26 * http://www.pcisys.net/~melanson/codecs/
27 *
28 * Supports: PAL8 (RGB 8bpp, paletted)
29 * : BGR24 (RGB 24bpp) (can also output it as RGB32)
30 * : RGB32 (RGB 32bpp, 4th plane is probably alpha and it's ignored)
31 *
32 */
33
34 #include <stdio.h>
35 #include <stdlib.h>
36 #include <string.h>
37
38 #include "libavutil/internal.h"
39 #include "libavutil/intreadwrite.h"
40 #include "avcodec.h"
41 #include "internal.h"
42
43
44 static const enum AVPixelFormat pixfmt_rgb24[] = {
45 AV_PIX_FMT_BGR24, AV_PIX_FMT_RGB32, AV_PIX_FMT_NONE };
46
47 typedef struct EightBpsContext {
48 AVCodecContext *avctx;
49 AVFrame pic;
50
51 unsigned char planes;
52 unsigned char planemap[4];
53
54 uint32_t pal[256];
55 } EightBpsContext;
56
57 static int decode_frame(AVCodecContext *avctx, void *data,
58 int *got_frame, AVPacket *avpkt)
59 {
60 const uint8_t *buf = avpkt->data;
61 int buf_size = avpkt->size;
62 EightBpsContext * const c = avctx->priv_data;
63 const unsigned char *encoded = buf;
64 unsigned char *pixptr, *pixptr_end;
65 unsigned int height = avctx->height; // Real image height
66 unsigned int dlen, p, row;
67 const unsigned char *lp, *dp;
68 unsigned char count;
69 unsigned int px_inc;
70 unsigned int planes = c->planes;
71 unsigned char *planemap = c->planemap;
72 int ret;
73
74 if (c->pic.data[0])
75 avctx->release_buffer(avctx, &c->pic);
76
77 c->pic.reference = 0;
78 c->pic.buffer_hints = FF_BUFFER_HINTS_VALID;
79 if ((ret = ff_get_buffer(avctx, &c->pic)) < 0) {
80 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
81 return ret;
82 }
83
84 /* Set data pointer after line lengths */
85 dp = encoded + planes * (height << 1);
86
87 /* Ignore alpha plane, don't know what to do with it */
88 if (planes == 4)
89 planes--;
90
91 px_inc = planes + (avctx->pix_fmt == AV_PIX_FMT_RGB32);
92
93 for (p = 0; p < planes; p++) {
94 /* Lines length pointer for this plane */
95 lp = encoded + p * (height << 1);
96
97 /* Decode a plane */
98 for (row = 0; row < height; row++) {
99 pixptr = c->pic.data[0] + row * c->pic.linesize[0] + planemap[p];
100 pixptr_end = pixptr + c->pic.linesize[0];
101 dlen = av_be2ne16(*(const unsigned short *)(lp + row * 2));
102 /* Decode a row of this plane */
103 while (dlen > 0) {
104 if (dp + 1 >= buf + buf_size)
105 return AVERROR_INVALIDDATA;
106 if ((count = *dp++) <= 127) {
107 count++;
108 dlen -= count + 1;
109 if (pixptr + count * px_inc > pixptr_end)
110 break;
111 if (dp + count > buf + buf_size)
112 return AVERROR_INVALIDDATA;
113 while (count--) {
114 *pixptr = *dp++;
115 pixptr += px_inc;
116 }
117 } else {
118 count = 257 - count;
119 if (pixptr + count * px_inc > pixptr_end)
120 break;
121 while (count--) {
122 *pixptr = *dp;
123 pixptr += px_inc;
124 }
125 dp++;
126 dlen -= 2;
127 }
128 }
129 }
130 }
131
132 if (avctx->bits_per_coded_sample <= 8) {
133 const uint8_t *pal = av_packet_get_side_data(avpkt,
134 AV_PKT_DATA_PALETTE,
135 NULL);
136 if (pal) {
137 c->pic.palette_has_changed = 1;
138 memcpy(c->pal, pal, AVPALETTE_SIZE);
139 }
140
141 memcpy (c->pic.data[1], c->pal, AVPALETTE_SIZE);
142 }
143
144 *got_frame = 1;
145 *(AVFrame*)data = c->pic;
146
147 /* always report that the buffer was completely consumed */
148 return buf_size;
149 }
150
151 static av_cold int decode_init(AVCodecContext *avctx)
152 {
153 EightBpsContext * const c = avctx->priv_data;
154
155 c->avctx = avctx;
156 c->pic.data[0] = NULL;
157
158 switch (avctx->bits_per_coded_sample) {
159 case 8:
160 avctx->pix_fmt = AV_PIX_FMT_PAL8;
161 c->planes = 1;
162 c->planemap[0] = 0; // 1st plane is palette indexes
163 break;
164 case 24:
165 avctx->pix_fmt = avctx->get_format(avctx, pixfmt_rgb24);
166 c->planes = 3;
167 c->planemap[0] = 2; // 1st plane is red
168 c->planemap[1] = 1; // 2nd plane is green
169 c->planemap[2] = 0; // 3rd plane is blue
170 break;
171 case 32:
172 avctx->pix_fmt = AV_PIX_FMT_RGB32;
173 c->planes = 4;
174 #if HAVE_BIGENDIAN
175 c->planemap[0] = 1; // 1st plane is red
176 c->planemap[1] = 2; // 2nd plane is green
177 c->planemap[2] = 3; // 3rd plane is blue
178 c->planemap[3] = 0; // 4th plane is alpha???
179 #else
180 c->planemap[0] = 2; // 1st plane is red
181 c->planemap[1] = 1; // 2nd plane is green
182 c->planemap[2] = 0; // 3rd plane is blue
183 c->planemap[3] = 3; // 4th plane is alpha???
184 #endif
185 break;
186 default:
187 av_log(avctx, AV_LOG_ERROR, "Error: Unsupported color depth: %u.\n",
188 avctx->bits_per_coded_sample);
189 return AVERROR_INVALIDDATA;
190 }
191
192 return 0;
193 }
194
195 static av_cold int decode_end(AVCodecContext *avctx)
196 {
197 EightBpsContext * const c = avctx->priv_data;
198
199 if (c->pic.data[0])
200 avctx->release_buffer(avctx, &c->pic);
201
202 return 0;
203 }
204
205 AVCodec ff_eightbps_decoder = {
206 .name = "8bps",
207 .type = AVMEDIA_TYPE_VIDEO,
208 .id = AV_CODEC_ID_8BPS,
209 .priv_data_size = sizeof(EightBpsContext),
210 .init = decode_init,
211 .close = decode_end,
212 .decode = decode_frame,
213 .capabilities = CODEC_CAP_DR1,
214 .long_name = NULL_IF_CONFIG_SMALL("QuickTime 8BPS video"),
215 };