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
37#include "libavutil/intreadwrite.h"
38#include "avcodec.h"
39
40
41static const enum PixelFormat pixfmt_rgb24[] = {PIX_FMT_BGR24, PIX_FMT_RGB32, PIX_FMT_NONE};
42
43/*
44 * Decoder context
45 */
46typedef struct EightBpsContext {
47
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
58/*
59 *
60 * Decode a frame
61 *
62 */
63static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt)
64{
65        const uint8_t *buf = avpkt->data;
66        int buf_size = avpkt->size;
67        EightBpsContext * const c = avctx->priv_data;
68        const unsigned char *encoded = buf;
69        unsigned char *pixptr, *pixptr_end;
70        unsigned int height = avctx->height; // Real image height
71        unsigned int dlen, p, row;
72        const unsigned char *lp, *dp;
73        unsigned char count;
74        unsigned int px_inc;
75        unsigned int planes = c->planes;
76        unsigned char *planemap = c->planemap;
77
78        if(c->pic.data[0])
79                avctx->release_buffer(avctx, &c->pic);
80
81        c->pic.reference = 0;
82        c->pic.buffer_hints = FF_BUFFER_HINTS_VALID;
83        if(avctx->get_buffer(avctx, &c->pic) < 0){
84                av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
85                return -1;
86        }
87
88        /* Set data pointer after line lengths */
89        dp = encoded + planes * (height << 1);
90
91        /* Ignore alpha plane, don't know what to do with it */
92        if (planes == 4)
93                planes--;
94
95        px_inc = planes + (avctx->pix_fmt == PIX_FMT_RGB32);
96
97        for (p = 0; p < planes; p++) {
98                /* Lines length pointer for this plane */
99                lp = encoded + p * (height << 1);
100
101                /* Decode a plane */
102                for(row = 0; row < height; row++) {
103                        pixptr = c->pic.data[0] + row * c->pic.linesize[0] + planemap[p];
104                        pixptr_end = pixptr + c->pic.linesize[0];
105                        dlen = av_be2ne16(*(const unsigned short *)(lp+row*2));
106                        /* Decode a row of this plane */
107                        while(dlen > 0) {
108                                if(dp + 1 >= buf+buf_size) return -1;
109                                if ((count = *dp++) <= 127) {
110                                        count++;
111                                        dlen -= count + 1;
112                                        if (pixptr + count * px_inc > pixptr_end)
113                                            break;
114                                        if(dp + count > buf+buf_size) return -1;
115                                        while(count--) {
116                                                *pixptr = *dp++;
117                                                pixptr += px_inc;
118                                        }
119                                } else {
120                                        count = 257 - count;
121                                        if (pixptr + count * px_inc > pixptr_end)
122                                            break;
123                                        while(count--) {
124                                                *pixptr = *dp;
125                                                pixptr += px_inc;
126                                        }
127                                        dp++;
128                                        dlen -= 2;
129                                }
130                        }
131                }
132        }
133
134        if (avctx->bits_per_coded_sample <= 8) {
135                const uint8_t *pal = av_packet_get_side_data(avpkt,
136                                                             AV_PKT_DATA_PALETTE,
137                                                             NULL);
138                if (pal) {
139                        c->pic.palette_has_changed = 1;
140                        memcpy(c->pal, pal, AVPALETTE_SIZE);
141                }
142
143                memcpy (c->pic.data[1], c->pal, AVPALETTE_SIZE);
144        }
145
146        *data_size = sizeof(AVFrame);
147        *(AVFrame*)data = c->pic;
148
149        /* always report that the buffer was completely consumed */
150        return buf_size;
151}
152
153
154/*
155 *
156 * Init 8BPS decoder
157 *
158 */
159static av_cold int decode_init(AVCodecContext *avctx)
160{
161        EightBpsContext * const c = avctx->priv_data;
162
163        c->avctx = avctx;
164
165        c->pic.data[0] = NULL;
166
167        switch (avctx->bits_per_coded_sample) {
168                case 8:
169                        avctx->pix_fmt = PIX_FMT_PAL8;
170                        c->planes = 1;
171                        c->planemap[0] = 0; // 1st plane is palette indexes
172                        break;
173                case 24:
174                        avctx->pix_fmt = avctx->get_format(avctx, pixfmt_rgb24);
175                        c->planes = 3;
176                        c->planemap[0] = 2; // 1st plane is red
177                        c->planemap[1] = 1; // 2nd plane is green
178                        c->planemap[2] = 0; // 3rd plane is blue
179                        break;
180                case 32:
181                        avctx->pix_fmt = PIX_FMT_RGB32;
182                        c->planes = 4;
183#if HAVE_BIGENDIAN
184                        c->planemap[0] = 1; // 1st plane is red
185                        c->planemap[1] = 2; // 2nd plane is green
186                        c->planemap[2] = 3; // 3rd plane is blue
187                        c->planemap[3] = 0; // 4th plane is alpha???
188#else
189                        c->planemap[0] = 2; // 1st plane is red
190                        c->planemap[1] = 1; // 2nd plane is green
191                        c->planemap[2] = 0; // 3rd plane is blue
192                        c->planemap[3] = 3; // 4th plane is alpha???
193#endif
194                        break;
195                default:
196                        av_log(avctx, AV_LOG_ERROR, "Error: Unsupported color depth: %u.\n", avctx->bits_per_coded_sample);
197                        return -1;
198        }
199
200  return 0;
201}
202
203
204
205
206/*
207 *
208 * Uninit 8BPS decoder
209 *
210 */
211static av_cold int decode_end(AVCodecContext *avctx)
212{
213        EightBpsContext * const c = avctx->priv_data;
214
215        if (c->pic.data[0])
216                avctx->release_buffer(avctx, &c->pic);
217
218        return 0;
219}
220
221
222
223AVCodec ff_eightbps_decoder = {
224    .name           = "8bps",
225    .type           = AVMEDIA_TYPE_VIDEO,
226    .id             = CODEC_ID_8BPS,
227    .priv_data_size = sizeof(EightBpsContext),
228    .init           = decode_init,
229    .close          = decode_end,
230    .decode         = decode_frame,
231    .capabilities   = CODEC_CAP_DR1,
232    .long_name      = NULL_IF_CONFIG_SMALL("QuickTime 8BPS video"),
233};
234