path: root/libavcodec/8bps.c (plain)
blob: aa2318fa2d817288ba6bc604076e04b0fa9c19c1

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
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	int 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
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