1/*
2 * Quicktime Planar RGB (8BPS) Video Decoder
3 * Copyright (C) 2003 Roberto Togni
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 * 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} EightBpsContext;
54
55
56/*
57 *
58 * Decode a frame
59 *
60 */
61static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt)
62{
63        const uint8_t *buf = avpkt->data;
64        int buf_size = avpkt->size;
65        EightBpsContext * const c = avctx->priv_data;
66        const unsigned char *encoded = buf;
67        unsigned char *pixptr, *pixptr_end;
68        unsigned int height = avctx->height; // Real image height
69        unsigned int dlen, p, row;
70        const unsigned char *lp, *dp;
71        unsigned char count;
72        unsigned int px_inc;
73        unsigned int planes = c->planes;
74        unsigned char *planemap = c->planemap;
75
76        if(c->pic.data[0])
77                avctx->release_buffer(avctx, &c->pic);
78
79        c->pic.reference = 0;
80        c->pic.buffer_hints = FF_BUFFER_HINTS_VALID;
81        if(avctx->get_buffer(avctx, &c->pic) < 0){
82                av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
83                return -1;
84        }
85
86        /* Set data pointer after line lengths */
87        dp = encoded + planes * (height << 1);
88
89        /* Ignore alpha plane, don't know what to do with it */
90        if (planes == 4)
91                planes--;
92
93        px_inc = planes + (avctx->pix_fmt == PIX_FMT_RGB32);
94
95        for (p = 0; p < planes; p++) {
96                /* Lines length pointer for this plane */
97                lp = encoded + p * (height << 1);
98
99                /* Decode a plane */
100                for(row = 0; row < height; row++) {
101                        pixptr = c->pic.data[0] + row * c->pic.linesize[0] + planemap[p];
102                        pixptr_end = pixptr + c->pic.linesize[0];
103                        dlen = be2me_16(*(const unsigned short *)(lp+row*2));
104                        /* Decode a row of this plane */
105                        while(dlen > 0) {
106                                if(dp + 1 >= buf+buf_size) return -1;
107                                if ((count = *dp++) <= 127) {
108                                        count++;
109                                        dlen -= count + 1;
110                                        if (pixptr + count * px_inc > pixptr_end)
111                                            break;
112                                        if(dp + count > buf+buf_size) return -1;
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->palctrl) {
133                memcpy (c->pic.data[1], avctx->palctrl->palette, AVPALETTE_SIZE);
134                if (avctx->palctrl->palette_changed) {
135                        c->pic.palette_has_changed = 1;
136                        avctx->palctrl->palette_changed = 0;
137                } else
138                        c->pic.palette_has_changed = 0;
139        }
140
141        *data_size = sizeof(AVFrame);
142        *(AVFrame*)data = c->pic;
143
144        /* always report that the buffer was completely consumed */
145        return buf_size;
146}
147
148
149/*
150 *
151 * Init 8BPS decoder
152 *
153 */
154static av_cold int decode_init(AVCodecContext *avctx)
155{
156        EightBpsContext * const c = avctx->priv_data;
157
158        c->avctx = avctx;
159
160        c->pic.data[0] = NULL;
161
162        switch (avctx->bits_per_coded_sample) {
163                case 8:
164                        avctx->pix_fmt = PIX_FMT_PAL8;
165                        c->planes = 1;
166                        c->planemap[0] = 0; // 1st plane is palette indexes
167                        if (avctx->palctrl == NULL) {
168                                av_log(avctx, AV_LOG_ERROR, "Error: PAL8 format but no palette from demuxer.\n");
169                                return -1;
170                        }
171                        break;
172                case 24:
173                        avctx->pix_fmt = avctx->get_format(avctx, pixfmt_rgb24);
174                        c->planes = 3;
175                        c->planemap[0] = 2; // 1st plane is red
176                        c->planemap[1] = 1; // 2nd plane is green
177                        c->planemap[2] = 0; // 3rd plane is blue
178                        break;
179                case 32:
180                        avctx->pix_fmt = PIX_FMT_RGB32;
181                        c->planes = 4;
182#if HAVE_BIGENDIAN
183                        c->planemap[0] = 1; // 1st plane is red
184                        c->planemap[1] = 2; // 2nd plane is green
185                        c->planemap[2] = 3; // 3rd plane is blue
186                        c->planemap[3] = 0; // 4th plane is alpha???
187#else
188                        c->planemap[0] = 2; // 1st plane is red
189                        c->planemap[1] = 1; // 2nd plane is green
190                        c->planemap[2] = 0; // 3rd plane is blue
191                        c->planemap[3] = 3; // 4th plane is alpha???
192#endif
193                        break;
194                default:
195                        av_log(avctx, AV_LOG_ERROR, "Error: Unsupported color depth: %u.\n", avctx->bits_per_coded_sample);
196                        return -1;
197        }
198
199  return 0;
200}
201
202
203
204
205/*
206 *
207 * Uninit 8BPS decoder
208 *
209 */
210static av_cold int decode_end(AVCodecContext *avctx)
211{
212        EightBpsContext * const c = avctx->priv_data;
213
214        if (c->pic.data[0])
215                avctx->release_buffer(avctx, &c->pic);
216
217        return 0;
218}
219
220
221
222AVCodec eightbps_decoder = {
223        "8bps",
224        AVMEDIA_TYPE_VIDEO,
225        CODEC_ID_8BPS,
226        sizeof(EightBpsContext),
227        decode_init,
228        NULL,
229        decode_end,
230        decode_frame,
231        CODEC_CAP_DR1,
232        .long_name = NULL_IF_CONFIG_SMALL("QuickTime 8BPS video"),
233};
234