path: root/libavformat/ttaenc.c (plain)
blob: fdce1e3dc1c0fb65f436dd8a76509ef8925df26c

1	/*
2	* True Audio (TTA) muxer
3	* Copyright (c) 2016 James Almer
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/crc.h"
23	#include "libavutil/intreadwrite.h"
24
25	#include "apetag.h"
26	#include "avformat.h"
27	#include "avio_internal.h"
28	#include "internal.h"
29
30	typedef struct TTAMuxContext {
31	AVIOContext *seek_table;
32	AVIOContext *data;
33	uint32_t nb_samples;
34	int frame_size;
35	int last_frame;
36	} TTAMuxContext;
37
38	static int tta_write_header(AVFormatContext *s)
39	{
40	TTAMuxContext *tta = s->priv_data;
41	AVCodecParameters *par = s->streams[0]->codecpar;
42	int ret;
43
44	if (s->nb_streams != 1) {
45	av_log(s, AV_LOG_ERROR, "Only one stream is supported\n");
46	return AVERROR(EINVAL);
47	}
48	if (par->codec_id != AV_CODEC_ID_TTA) {
49	av_log(s, AV_LOG_ERROR, "Unsupported codec\n");
50	return AVERROR(EINVAL);
51	}
52	if (par->extradata && par->extradata_size < 22) {
53	av_log(s, AV_LOG_ERROR, "Invalid TTA extradata\n");
54	return AVERROR_INVALIDDATA;
55	}
56
57	if ((ret = avio_open_dyn_buf(&tta->seek_table)) < 0)
58	return ret;
59	if ((ret = avio_open_dyn_buf(&tta->data)) < 0) {
60	ffio_free_dyn_buf(&tta->seek_table);
61	return ret;
62	}
63
64	/* Ignore most extradata information if present. It can be innacurate
65	if for example remuxing from Matroska */
66	ffio_init_checksum(s->pb, ff_crcEDB88320_update, UINT32_MAX);
67	ffio_init_checksum(tta->seek_table, ff_crcEDB88320_update, UINT32_MAX);
68	avio_write(s->pb, "TTA1", 4);
69	avio_wl16(s->pb, par->extradata ? AV_RL16(par->extradata + 4) : 1);
70	avio_wl16(s->pb, par->channels);
71	avio_wl16(s->pb, par->bits_per_raw_sample);
72	avio_wl32(s->pb, par->sample_rate);
73	/* Prevent overflow */
74	if (par->sample_rate > 0x7FFFFFu) {
75	av_log(s, AV_LOG_ERROR, "Sample rate too large\n");
76	return AVERROR(EINVAL);
77	}
78	tta->frame_size = par->sample_rate * 256 / 245;
79	avpriv_set_pts_info(s->streams[0], 64, 1, par->sample_rate);
80
81	return 0;
82	}
83
84	static int tta_write_packet(AVFormatContext *s, AVPacket *pkt)
85	{
86	TTAMuxContext *tta = s->priv_data;
87
88	avio_write(tta->data, pkt->data, pkt->size);
89	avio_wl32(tta->seek_table, pkt->size);
90	tta->nb_samples += pkt->duration;
91
92	if (tta->frame_size != pkt->duration) {
93	if (tta->last_frame) {
94	/* Two frames with a different duration than the default frame
95	size means the TTA stream comes from a faulty container, and
96	there's no way the last frame duration will be correct. */
97	av_log(s, AV_LOG_ERROR, "Invalid frame durations\n");
98
99	return AVERROR_INVALIDDATA;
100	}
101	/* First frame with a different duration than the default frame size.
102	Assume it's the last frame in the stream and continue. */
103	tta->last_frame++;
104	}
105
106	return 0;
107	}
108
109	static int tta_write_trailer(AVFormatContext *s)
110	{
111	TTAMuxContext *tta = s->priv_data;
112	uint8_t *ptr;
113	unsigned int crc;
114	int size;
115
116	avio_wl32(s->pb, tta->nb_samples);
117	crc = ffio_get_checksum(s->pb) ^ UINT32_MAX;
118	avio_wl32(s->pb, crc);
119
120	/* Write Seek table */
121	crc = ffio_get_checksum(tta->seek_table) ^ UINT32_MAX;
122	avio_wl32(tta->seek_table, crc);
123	size = avio_close_dyn_buf(tta->seek_table, &ptr);
124	avio_write(s->pb, ptr, size);
125	av_free(ptr);
126
127	/* Write audio data */
128	size = avio_close_dyn_buf(tta->data, &ptr);
129	avio_write(s->pb, ptr, size);
130	av_free(ptr);
131
132	ff_ape_write_tag(s);
133	avio_flush(s->pb);
134
135	return 0;
136	}
137
138	AVOutputFormat ff_tta_muxer = {
139	.name = "tta",
140	.long_name = NULL_IF_CONFIG_SMALL("TTA (True Audio)"),
141	.mime_type = "audio/x-tta",
142	.extensions = "tta",
143	.priv_data_size = sizeof(TTAMuxContext),
144	.audio_codec = AV_CODEC_ID_TTA,
145	.video_codec = AV_CODEC_ID_NONE,
146	.write_header = tta_write_header,
147	.write_packet = tta_write_packet,
148	.write_trailer = tta_write_trailer,
149	};
150