/src/ffmpeg/libavformat/cdxl.c

Source
/*
 * CDXL demuxer
 * Copyright (c) 2011-2012 Paul B Mahol
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include "libavutil/channel_layout.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/parseutils.h"
#include "libavutil/opt.h"
#include "avformat.h"
#include "demux.h"
#include "internal.h"

#define CDXL_HEADER_SIZE 32

typedef struct CDXLDemuxContext {
    AVClass     *class;
    int         read_chunk;
    AVRational  frate;
    int         srate;
    AVRational  frame_rate;
    int         sample_rate;
    uint8_t     header[CDXL_HEADER_SIZE];
    int         video_stream_index;
    int         audio_stream_index;
    int64_t     filesize;
    int64_t     pos;
} CDXLDemuxContext;

static int cdxl_read_probe(const AVProbeData *p)
{
    int score = AVPROBE_SCORE_EXTENSION + 10;
    const uint8_t *buf = p->buf;

    if (p->buf_size < CDXL_HEADER_SIZE)
        return 0;

    /* check type */
    if (buf[0] > 1)
        return 0;

    /* reserved bytes should always be set to 0 */
    if (AV_RL24(&buf[29]))
        return 0;

    /* check palette size */
    if (!AV_RN16(&buf[20]))
        return 0;
    if (buf[0] == 1 && AV_RB16(&buf[20]) > 512)
        return 0;
    if (buf[0] == 0 && AV_RB16(&buf[20]) > 768)
        return 0;

    if (!AV_RN16(&buf[22]) && AV_RN16(&buf[24]))
        return 0;

    if (buf[0] == 0 && (!buf[26] || !AV_RB16(&buf[24])))
        return 0;

    /* check number of planes */
    if (buf[19] != 6 && buf[19] != 8 && buf[19] != 24)
        return 0;

    if (buf[18])
        return 0;

    /* check widh and height */
    if (AV_RB16(&buf[14]) > 640 || AV_RB16(&buf[16]) > 480 ||
        AV_RB16(&buf[14]) == 0 || AV_RB16(&buf[16]) == 0)
        return 0;

    /* chunk size */
    if (AV_RB32(&buf[2]) <= AV_RB16(&buf[20]) + AV_RB16(&buf[22]) * (1 + !!(buf[1] & 0x10)) + CDXL_HEADER_SIZE)
        return 0;

    /* previous chunk size */
    if (AV_RN32(&buf[6]))
        score /= 2;

    /* current frame number, usually starts from 1 */
    if (AV_RB32(&buf[10]) != 1)
        score /= 2;

    return score;
}

static int cdxl_read_header(AVFormatContext *s)
{
    CDXLDemuxContext *cdxl = s->priv_data;

    cdxl->read_chunk         =  0;
    cdxl->video_stream_index = -1;
    cdxl->audio_stream_index = -1;

    cdxl->filesize = avio_size(s->pb);

    s->ctx_flags |= AVFMTCTX_NOHEADER;

    return 0;
}

static int cdxl_read_packet(AVFormatContext *s, AVPacket *pkt)
{
    CDXLDemuxContext *cdxl = s->priv_data;
    AVIOContext *pb = s->pb;
    uint32_t current_size, video_size, image_size;
    uint16_t audio_size, palette_size, width, height;
    int      channels, type, format, ret;

    if (avio_feof(pb))
        return AVERROR_EOF;

    if (!cdxl->read_chunk) {
        cdxl->pos = avio_tell(pb);
        if (avio_read(pb, cdxl->header, CDXL_HEADER_SIZE) != CDXL_HEADER_SIZE)
            return AVERROR_EOF;
    }
    if (cdxl->header[0] > 1) {
        av_log(s, AV_LOG_ERROR, "unsupported cdxl file\n");
        return AVERROR_INVALIDDATA;
    }

    type         = cdxl->header[0];
    channels     = 1 + !!(cdxl->header[1] & 0x10);
    format       = cdxl->header[1] & 0xE0;
    current_size = AV_RB32(&cdxl->header[2]);
    width        = AV_RB16(&cdxl->header[14]);
    height       = AV_RB16(&cdxl->header[16]);
    palette_size = AV_RB16(&cdxl->header[20]);
    audio_size   = AV_RB16(&cdxl->header[22]) * channels;
    cdxl->srate  = AV_RB16(&cdxl->header[24]);
    if (!cdxl->srate && audio_size)
        cdxl->srate = cdxl->sample_rate;
    cdxl->frate.num = cdxl->header[26];
    cdxl->frate.den = 1;
    if (cdxl->header[19] == 0 ||
        FFALIGN(width, 16) * (uint64_t)height * cdxl->header[19] > INT_MAX)
        return AVERROR_INVALIDDATA;
    if (format == 0x20)
        image_size = width * height * cdxl->header[19] / 8;
    else
        image_size = FFALIGN(width, 16) * height * cdxl->header[19] / 8;
    video_size   = palette_size + image_size;

    if ((type == 1 && palette_size > 512) ||
        (type == 0 && palette_size > 768))
        return AVERROR_INVALIDDATA;
    if (current_size < (uint64_t)audio_size + video_size + CDXL_HEADER_SIZE)
        return AVERROR_INVALIDDATA;

    if (!cdxl->frate.num && audio_size && cdxl->srate > 0) {
        cdxl->frate = (AVRational){ cdxl->srate, audio_size };
    } else if (!cdxl->frate.num) {
        cdxl->frate = cdxl->frame_rate;
    }

    if (cdxl->read_chunk && audio_size) {
        if (cdxl->audio_stream_index == -1) {
            AVStream *st = avformat_new_stream(s, NULL);
            if (!st)
                return AVERROR(ENOMEM);

            st->codecpar->codec_type    = AVMEDIA_TYPE_AUDIO;
            st->codecpar->codec_tag     = 0;
            st->codecpar->codec_id      = AV_CODEC_ID_PCM_S8_PLANAR;
            av_channel_layout_default(&st->codecpar->ch_layout, channels);
            st->codecpar->sample_rate= cdxl->srate;
            st->start_time           = 0;
            cdxl->audio_stream_index = st->index;
            avpriv_set_pts_info(st, 64, 1, cdxl->srate);
            if (current_size && cdxl->filesize > 0 && audio_size > 0)
                st->duration = (cdxl->filesize / current_size) * audio_size / channels;
        }

        ret = av_get_packet(pb, pkt, audio_size);
        if (ret < 0)
            return ret;
        pkt->stream_index = cdxl->audio_stream_index;
        pkt->pos          = cdxl->pos;
        pkt->duration     = audio_size / channels;
        cdxl->read_chunk  = 0;
    } else {
        if (cdxl->video_stream_index == -1) {
            AVStream *st = avformat_new_stream(s, NULL);
            if (!st)
                return AVERROR(ENOMEM);

            st->codecpar->codec_type    = AVMEDIA_TYPE_VIDEO;
            st->codecpar->codec_tag     = 0;
            st->codecpar->codec_id      = AV_CODEC_ID_CDXL;
            st->codecpar->width         = width;
            st->codecpar->height        = height;

            if (current_size && cdxl->filesize > 0)
                st->nb_frames = cdxl->filesize / current_size;
            st->start_time           = 0;
            cdxl->video_stream_index = st->index;
            avpriv_set_pts_info(st, 64, cdxl->frate.den, cdxl->frate.num);
        }

        if ((ret = av_new_packet(pkt, video_size + CDXL_HEADER_SIZE)) < 0)
            return ret;
        memcpy(pkt->data, cdxl->header, CDXL_HEADER_SIZE);
        ret = avio_read(pb, pkt->data + CDXL_HEADER_SIZE, video_size);
        if (ret < 0) {
            return ret;
        }
        av_shrink_packet(pkt, CDXL_HEADER_SIZE + ret);
        pkt->stream_index  = cdxl->video_stream_index;
        pkt->flags        |= AV_PKT_FLAG_KEY;
        pkt->pos           = cdxl->pos;
        pkt->duration      = 1;
        cdxl->read_chunk   = audio_size;
    }

    if (!cdxl->read_chunk)
        avio_skip(pb, current_size - audio_size - video_size - CDXL_HEADER_SIZE);
    return ret;
}

static int read_seek(AVFormatContext *s, int stream_index,
                     int64_t timestamp, int flags)
{
    CDXLDemuxContext *cdxl = s->priv_data;

    cdxl->read_chunk = 0;

    return -1;
}

#define OFFSET(x) offsetof(CDXLDemuxContext, x)
static const AVOption cdxl_options[] = {
    { "sample_rate", "", OFFSET(sample_rate), AV_OPT_TYPE_INT, { .i64=11025 }, 8000, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
    { "frame_rate", "", OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, { .str="15" }, 1, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
    { NULL },
};

static const AVClass cdxl_demuxer_class = {
    .class_name = "CDXL demuxer",
    .item_name  = av_default_item_name,
    .option     = cdxl_options,
    .version    = LIBAVUTIL_VERSION_INT,
};

const FFInputFormat ff_cdxl_demuxer = {
    .p.name         = "cdxl",
    .p.long_name    = NULL_IF_CONFIG_SMALL("Commodore CDXL video"),
    .p.priv_class   = &cdxl_demuxer_class,
    .p.extensions   = "cdxl,xl",
    .p.flags        = AVFMT_GENERIC_INDEX,
    .priv_data_size = sizeof(CDXLDemuxContext),
    .read_probe     = cdxl_read_probe,
    .read_header    = cdxl_read_header,
    .read_packet    = cdxl_read_packet,
    .read_seek      = read_seek,
};

Coverage Report

Created: 2026-07-25 07:52

Line	Count	Source
1		/*
2		* CDXL demuxer
3		* Copyright (c) 2011-2012 Paul B Mahol
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		#include "libavutil/channel_layout.h"
23		#include "libavutil/intreadwrite.h"
24		#include "libavutil/parseutils.h"
25		#include "libavutil/opt.h"
26		#include "avformat.h"
27		#include "demux.h"
28		#include "internal.h"
29
30	4.16M	#define CDXL_HEADER_SIZE 32
31
32		typedef struct CDXLDemuxContext {
33		AVClass *class;
34		int read_chunk;
35		AVRational frate;
36		int srate;
37		AVRational frame_rate;
38		int sample_rate;
39		uint8_t header[CDXL_HEADER_SIZE];
40		int video_stream_index;
41		int audio_stream_index;
42		int64_t filesize;
43		int64_t pos;
44		} CDXLDemuxContext;
45
46		static int cdxl_read_probe(const AVProbeData *p)
47	967k	{
48	967k	int score = AVPROBE_SCORE_EXTENSION + 10;
49	967k	const uint8_t *buf = p->buf;
50
51	967k	if (p->buf_size < CDXL_HEADER_SIZE)
52	209k	return 0;
53
54		/* check type */
55	758k	if (buf[0] > 1)
56	585k	return 0;
57
58		/* reserved bytes should always be set to 0 */
59	173k	if (AV_RL24(&buf[29]))
60	119k	return 0;
61
62		/* check palette size */
63	54.1k	if (!AV_RN16(&buf[20]))
64	34.3k	return 0;
65	19.8k	if (buf[0] == 1 && AV_RB16(&buf[20]) > 512)
66	3.06k	return 0;
67	16.7k	if (buf[0] == 0 && AV_RB16(&buf[20]) > 768)
68	7.84k	return 0;
69
70	8.89k	if (!AV_RN16(&buf[22]) && AV_RN16(&buf[24]))
71	1.17k	return 0;
72
73	7.72k	if (buf[0] == 0 && (!buf[26] \|\| !AV_RB16(&buf[24])))
74	2.45k	return 0;
75
76		/* check number of planes */
77	5.27k	if (buf[19] != 6 && buf[19] != 8 && buf[19] != 24)
78	2.31k	return 0;
79
80	2.96k	if (buf[18])
81	209	return 0;
82
83		/* check widh and height */
84	2.75k	if (AV_RB16(&buf[14]) > 640 \|\| AV_RB16(&buf[16]) > 480 \|\|
85	2.33k	AV_RB16(&buf[14]) == 0 \|\| AV_RB16(&buf[16]) == 0)
86	916	return 0;
87
88		/* chunk size */
89	1.83k	if (AV_RB32(&buf[2]) <= AV_RB16(&buf[20]) + AV_RB16(&buf[22]) * (1 + !!(buf[1] & 0x10)) + CDXL_HEADER_SIZE)
90	342	return 0;
91
92		/* previous chunk size */
93	1.49k	if (AV_RN32(&buf[6]))
94	1.21k	score /= 2;
95
96		/* current frame number, usually starts from 1 */
97	1.49k	if (AV_RB32(&buf[10]) != 1)
98	534	score /= 2;
99
100	1.49k	return score;
101	1.83k	}
102
103		static int cdxl_read_header(AVFormatContext *s)
104	2.00k	{
105	2.00k	CDXLDemuxContext *cdxl = s->priv_data;
106
107	2.00k	cdxl->read_chunk = 0;
108	2.00k	cdxl->video_stream_index = -1;
109	2.00k	cdxl->audio_stream_index = -1;
110
111	2.00k	cdxl->filesize = avio_size(s->pb);
112
113	2.00k	s->ctx_flags \|= AVFMTCTX_NOHEADER;
114
115	2.00k	return 0;
116	2.00k	}
117
118		static int cdxl_read_packet(AVFormatContext s, AVPacket pkt)
119	677k	{
120	677k	CDXLDemuxContext *cdxl = s->priv_data;
121	677k	AVIOContext *pb = s->pb;
122	677k	uint32_t current_size, video_size, image_size;
123	677k	uint16_t audio_size, palette_size, width, height;
124	677k	int channels, type, format, ret;
125
126	677k	if (avio_feof(pb))
127	2.14k	return AVERROR_EOF;
128
129	675k	if (!cdxl->read_chunk) {
130	361k	cdxl->pos = avio_tell(pb);
131	361k	if (avio_read(pb, cdxl->header, CDXL_HEADER_SIZE) != CDXL_HEADER_SIZE)
132	797	return AVERROR_EOF;
133	361k	}
134	675k	if (cdxl->header[0] > 1) {
135	113	av_log(s, AV_LOG_ERROR, "unsupported cdxl file\n");
136	113	return AVERROR_INVALIDDATA;
137	113	}
138
139	674k	type = cdxl->header[0];
140	674k	channels = 1 + !!(cdxl->header[1] & 0x10);
141	674k	format = cdxl->header[1] & 0xE0;
142	674k	current_size = AV_RB32(&cdxl->header[2]);
143	674k	width = AV_RB16(&cdxl->header[14]);
144	674k	height = AV_RB16(&cdxl->header[16]);
145	674k	palette_size = AV_RB16(&cdxl->header[20]);
146	674k	audio_size = AV_RB16(&cdxl->header[22]) * channels;
147	674k	cdxl->srate = AV_RB16(&cdxl->header[24]);
148	674k	if (!cdxl->srate && audio_size)
149	3.82k	cdxl->srate = cdxl->sample_rate;
150	674k	cdxl->frate.num = cdxl->header[26];
151	674k	cdxl->frate.den = 1;
152	674k	if (cdxl->header[19] == 0 \|\|
153	674k	FFALIGN(width, 16) * (uint64_t)height * cdxl->header[19] > INT_MAX)
154	119	return AVERROR_INVALIDDATA;
155	674k	if (format == 0x20)
156	1.03k	image_size = width * height * cdxl->header[19] / 8;
157	673k	else
158	673k	image_size = FFALIGN(width, 16) * height * cdxl->header[19] / 8;
159	674k	video_size = palette_size + image_size;
160
161	674k	if ((type == 1 && palette_size > 512) \|\|
162	674k	(type == 0 && palette_size > 768))
163	52	return AVERROR_INVALIDDATA;
164	674k	if (current_size < (uint64_t)audio_size + video_size + CDXL_HEADER_SIZE)
165	69	return AVERROR_INVALIDDATA;
166
167	674k	if (!cdxl->frate.num && audio_size && cdxl->srate > 0) {
168	313k	cdxl->frate = (AVRational){ cdxl->srate, audio_size };
169	361k	} else if (!cdxl->frate.num) {
170	36.5k	cdxl->frate = cdxl->frame_rate;
171	36.5k	}
172
173	674k	if (cdxl->read_chunk && audio_size) {
174	314k	if (cdxl->audio_stream_index == -1) {
175	1.35k	AVStream *st = avformat_new_stream(s, NULL);
176	1.35k	if (!st)
177	0	return AVERROR(ENOMEM);
178
179	1.35k	st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
180	1.35k	st->codecpar->codec_tag = 0;
181	1.35k	st->codecpar->codec_id = AV_CODEC_ID_PCM_S8_PLANAR;
182	1.35k	av_channel_layout_default(&st->codecpar->ch_layout, channels);
183	1.35k	st->codecpar->sample_rate= cdxl->srate;
184	1.35k	st->start_time = 0;
185	1.35k	cdxl->audio_stream_index = st->index;
186	1.35k	avpriv_set_pts_info(st, 64, 1, cdxl->srate);
187	1.35k	if (current_size && cdxl->filesize > 0 && audio_size > 0)
188	548	st->duration = (cdxl->filesize / current_size) * audio_size / channels;
189	1.35k	}
190
191	314k	ret = av_get_packet(pb, pkt, audio_size);
192	314k	if (ret < 0)
193	447	return ret;
194	313k	pkt->stream_index = cdxl->audio_stream_index;
195	313k	pkt->pos = cdxl->pos;
196	313k	pkt->duration = audio_size / channels;
197	313k	cdxl->read_chunk = 0;
198	360k	} else {
199	360k	if (cdxl->video_stream_index == -1) {
200	1.72k	AVStream *st = avformat_new_stream(s, NULL);
201	1.72k	if (!st)
202	0	return AVERROR(ENOMEM);
203
204	1.72k	st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
205	1.72k	st->codecpar->codec_tag = 0;
206	1.72k	st->codecpar->codec_id = AV_CODEC_ID_CDXL;
207	1.72k	st->codecpar->width = width;
208	1.72k	st->codecpar->height = height;
209
210	1.72k	if (current_size && cdxl->filesize > 0)
211	616	st->nb_frames = cdxl->filesize / current_size;
212	1.72k	st->start_time = 0;
213	1.72k	cdxl->video_stream_index = st->index;
214	1.72k	avpriv_set_pts_info(st, 64, cdxl->frate.den, cdxl->frate.num);
215	1.72k	}
216
217	360k	if ((ret = av_new_packet(pkt, video_size + CDXL_HEADER_SIZE)) < 0)
218	0	return ret;
219	360k	memcpy(pkt->data, cdxl->header, CDXL_HEADER_SIZE);
220	360k	ret = avio_read(pb, pkt->data + CDXL_HEADER_SIZE, video_size);
221	360k	if (ret < 0) {
222	101	return ret;
223	101	}
224	360k	av_shrink_packet(pkt, CDXL_HEADER_SIZE + ret);
225	360k	pkt->stream_index = cdxl->video_stream_index;
226	360k	pkt->flags \|= AV_PKT_FLAG_KEY;
227	360k	pkt->pos = cdxl->pos;
228	360k	pkt->duration = 1;
229	360k	cdxl->read_chunk = audio_size;
230	360k	}
231
232	674k	if (!cdxl->read_chunk)
233	359k	avio_skip(pb, current_size - audio_size - video_size - CDXL_HEADER_SIZE);
234	674k	return ret;
235	674k	}
236
237		static int read_seek(AVFormatContext *s, int stream_index,
238		int64_t timestamp, int flags)
239	0	{
240	0	CDXLDemuxContext *cdxl = s->priv_data;
241
242	0	cdxl->read_chunk = 0;
243
244	0	return -1;
245	0	}
246
247		#define OFFSET(x) offsetof(CDXLDemuxContext, x)
248		static const AVOption cdxl_options[] = {
249		{ "sample_rate", "", OFFSET(sample_rate), AV_OPT_TYPE_INT, { .i64=11025 }, 8000, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
250		{ "frame_rate", "", OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, { .str="15" }, 1, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
251		{ NULL },
252		};
253
254		static const AVClass cdxl_demuxer_class = {
255		.class_name = "CDXL demuxer",
256		.item_name = av_default_item_name,
257		.option = cdxl_options,
258		.version = LIBAVUTIL_VERSION_INT,
259		};
260
261		const FFInputFormat ff_cdxl_demuxer = {
262		.p.name = "cdxl",
263		.p.long_name = NULL_IF_CONFIG_SMALL("Commodore CDXL video"),
264		.p.priv_class = &cdxl_demuxer_class,
265		.p.extensions = "cdxl,xl",
266		.p.flags = AVFMT_GENERIC_INDEX,
267		.priv_data_size = sizeof(CDXLDemuxContext),
268		.read_probe = cdxl_read_probe,
269		.read_header = cdxl_read_header,
270		.read_packet = cdxl_read_packet,
271		.read_seek = read_seek,
272		};