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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 alpha)
31  */
32 
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <string.h>
36 
37 #include "libavutil/internal.h"
38 #include "libavutil/intreadwrite.h"
39 #include "avcodec.h"
40 #include "internal.h"
41 
42 
43 static const enum AVPixelFormat pixfmt_rgb24[] = {
44     AV_PIX_FMT_BGR24, AV_PIX_FMT_0RGB32, AV_PIX_FMT_NONE };
45 
46 typedef struct EightBpsContext {
47     AVCodecContext *avctx;
48 
49     unsigned char planes;
50     unsigned char planemap[4];
51 
52     uint32_t pal[256];
53 } EightBpsContext;
54 
decode_frame(AVCodecContext * avctx,void * data,int * got_frame,AVPacket * avpkt)55 static int decode_frame(AVCodecContext *avctx, void *data,
56                         int *got_frame, AVPacket *avpkt)
57 {
58     AVFrame *frame = data;
59     const uint8_t *buf = avpkt->data;
60     int buf_size       = avpkt->size;
61     EightBpsContext * const c = avctx->priv_data;
62     const unsigned char *encoded = buf;
63     unsigned char *pixptr, *pixptr_end;
64     unsigned int height = avctx->height; // Real image height
65     unsigned int dlen, p, row;
66     const unsigned char *lp, *dp, *ep;
67     unsigned char count;
68     unsigned int px_inc;
69     unsigned int planes     = c->planes;
70     unsigned char *planemap = c->planemap;
71     int ret;
72 
73     if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
74         return ret;
75 
76     ep = encoded + buf_size;
77 
78     /* Set data pointer after line lengths */
79     dp = encoded + planes * (height << 1);
80 
81     px_inc = planes + (avctx->pix_fmt == AV_PIX_FMT_0RGB32);
82 
83     for (p = 0; p < planes; p++) {
84         /* Lines length pointer for this plane */
85         lp = encoded + p * (height << 1);
86 
87         /* Decode a plane */
88         for (row = 0; row < height; row++) {
89             pixptr = frame->data[0] + row * frame->linesize[0] + planemap[p];
90             pixptr_end = pixptr + frame->linesize[0];
91             if (ep - lp < row * 2 + 2)
92                 return AVERROR_INVALIDDATA;
93             dlen = av_be2ne16(*(const unsigned short *)(lp + row * 2));
94             /* Decode a row of this plane */
95             while (dlen > 0) {
96                 if (ep - dp <= 1)
97                     return AVERROR_INVALIDDATA;
98                 if ((count = *dp++) <= 127) {
99                     count++;
100                     dlen -= count + 1;
101                     if (pixptr_end - pixptr < count * px_inc)
102                         break;
103                     if (ep - dp < count)
104                         return AVERROR_INVALIDDATA;
105                     while (count--) {
106                         *pixptr = *dp++;
107                         pixptr += px_inc;
108                     }
109                 } else {
110                     count = 257 - count;
111                     if (pixptr_end - pixptr < count * px_inc)
112                         break;
113                     while (count--) {
114                         *pixptr = *dp;
115                         pixptr += px_inc;
116                     }
117                     dp++;
118                     dlen -= 2;
119                 }
120             }
121         }
122     }
123 
124     if (avctx->bits_per_coded_sample <= 8) {
125         buffer_size_t size;
126         const uint8_t *pal = av_packet_get_side_data(avpkt,
127                                                      AV_PKT_DATA_PALETTE,
128                                                      &size);
129         if (pal && size == AVPALETTE_SIZE) {
130             frame->palette_has_changed = 1;
131             memcpy(c->pal, pal, AVPALETTE_SIZE);
132         } else if (pal) {
133             av_log(avctx, AV_LOG_ERROR, "Palette size %d is wrong\n", size);
134         }
135 
136         memcpy (frame->data[1], c->pal, AVPALETTE_SIZE);
137     }
138 
139     *got_frame = 1;
140 
141     /* always report that the buffer was completely consumed */
142     return buf_size;
143 }
144 
decode_init(AVCodecContext * avctx)145 static av_cold int decode_init(AVCodecContext *avctx)
146 {
147     EightBpsContext * const c = avctx->priv_data;
148 
149     c->avctx       = avctx;
150 
151     switch (avctx->bits_per_coded_sample) {
152     case 8:
153         avctx->pix_fmt = AV_PIX_FMT_PAL8;
154         c->planes      = 1;
155         c->planemap[0] = 0; // 1st plane is palette indexes
156         break;
157     case 24:
158         avctx->pix_fmt = ff_get_format(avctx, pixfmt_rgb24);
159         c->planes      = 3;
160         c->planemap[0] = 2; // 1st plane is red
161         c->planemap[1] = 1; // 2nd plane is green
162         c->planemap[2] = 0; // 3rd plane is blue
163         break;
164     case 32:
165         avctx->pix_fmt = AV_PIX_FMT_RGB32;
166         c->planes      = 4;
167         /* handle planemap setup later for decoding rgb24 data as rbg32 */
168         break;
169     default:
170         av_log(avctx, AV_LOG_ERROR, "Error: Unsupported color depth: %u.\n",
171                avctx->bits_per_coded_sample);
172         return AVERROR_INVALIDDATA;
173     }
174 
175     if (avctx->pix_fmt == AV_PIX_FMT_RGB32) {
176         c->planemap[0] = HAVE_BIGENDIAN ? 1 : 2; // 1st plane is red
177         c->planemap[1] = HAVE_BIGENDIAN ? 2 : 1; // 2nd plane is green
178         c->planemap[2] = HAVE_BIGENDIAN ? 3 : 0; // 3rd plane is blue
179         c->planemap[3] = HAVE_BIGENDIAN ? 0 : 3; // 4th plane is alpha
180     }
181     return 0;
182 }
183 
184 AVCodec ff_eightbps_decoder = {
185     .name           = "8bps",
186     .long_name      = NULL_IF_CONFIG_SMALL("QuickTime 8BPS video"),
187     .type           = AVMEDIA_TYPE_VIDEO,
188     .id             = AV_CODEC_ID_8BPS,
189     .priv_data_size = sizeof(EightBpsContext),
190     .init           = decode_init,
191     .decode         = decode_frame,
192     .capabilities   = AV_CODEC_CAP_DR1,
193 };
194