path: root/libavutil/samplefmt.h (plain)
blob: 8cd43ae8568a890f825299ee1e6d6f35ad1e5c5d

1	/*
2	* This file is part of FFmpeg.
3	*
4	* FFmpeg is free software; you can redistribute it and/or
5	* modify it under the terms of the GNU Lesser General Public
6	* License as published by the Free Software Foundation; either
7	* version 2.1 of the License, or (at your option) any later version.
8	*
9	* FFmpeg is distributed in the hope that it will be useful,
10	* but WITHOUT ANY WARRANTY; without even the implied warranty of
11	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12	* Lesser General Public License for more details.
13	*
14	* You should have received a copy of the GNU Lesser General Public
15	* License along with FFmpeg; if not, write to the Free Software
16	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17	*/
18
19	#ifndef AVUTIL_SAMPLEFMT_H
20	#define AVUTIL_SAMPLEFMT_H
21
22	#include <stdint.h>
23
24	#include "avutil.h"
25	#include "attributes.h"
26
27	/**
28	* @addtogroup lavu_audio
29	* @{
30	*
31	* @defgroup lavu_sampfmts Audio sample formats
32	*
33	* Audio sample format enumeration and related convenience functions.
34	* @{
35	*/
36
37	/**
38	* Audio sample formats
39	*
40	* - The data described by the sample format is always in native-endian order.
41	* Sample values can be expressed by native C types, hence the lack of a signed
42	* 24-bit sample format even though it is a common raw audio data format.
43	*
44	* - The floating-point formats are based on full volume being in the range
45	* [-1.0, 1.0]. Any values outside this range are beyond full volume level.
46	*
47	* - The data layout as used in av_samples_fill_arrays() and elsewhere in FFmpeg
48	* (such as AVFrame in libavcodec) is as follows:
49	*
50	* @par
51	* For planar sample formats, each audio channel is in a separate data plane,
52	* and linesize is the buffer size, in bytes, for a single plane. All data
53	* planes must be the same size. For packed sample formats, only the first data
54	* plane is used, and samples for each channel are interleaved. In this case,
55	* linesize is the buffer size, in bytes, for the 1 plane.
56	*
57	*/
58	enum AVSampleFormat {
59	AV_SAMPLE_FMT_NONE = -1,
60	AV_SAMPLE_FMT_U8, ///< unsigned 8 bits
61	AV_SAMPLE_FMT_S16, ///< signed 16 bits
62	AV_SAMPLE_FMT_S32, ///< signed 32 bits
63	AV_SAMPLE_FMT_FLT, ///< float
64	AV_SAMPLE_FMT_DBL, ///< double
65
66	AV_SAMPLE_FMT_U8P, ///< unsigned 8 bits, planar
67	AV_SAMPLE_FMT_S16P, ///< signed 16 bits, planar
68	AV_SAMPLE_FMT_S32P, ///< signed 32 bits, planar
69	AV_SAMPLE_FMT_FLTP, ///< float, planar
70	AV_SAMPLE_FMT_DBLP, ///< double, planar
71	AV_SAMPLE_FMT_S64, ///< signed 64 bits
72	AV_SAMPLE_FMT_S64P, ///< signed 64 bits, planar
73
74	AV_SAMPLE_FMT_NB ///< Number of sample formats. DO NOT USE if linking dynamically
75	};
76
77	/**
78	* Return the name of sample_fmt, or NULL if sample_fmt is not
79	* recognized.
80	*/
81	const char *av_get_sample_fmt_name(enum AVSampleFormat sample_fmt);
82
83	/**
84	* Return a sample format corresponding to name, or AV_SAMPLE_FMT_NONE
85	* on error.
86	*/
87	enum AVSampleFormat av_get_sample_fmt(const char *name);
88
89	/**
90	* Return the planar<->packed alternative form of the given sample format, or
91	* AV_SAMPLE_FMT_NONE on error. If the passed sample_fmt is already in the
92	* requested planar/packed format, the format returned is the same as the
93	* input.
94	*/
95	enum AVSampleFormat av_get_alt_sample_fmt(enum AVSampleFormat sample_fmt, int planar);
96
97	/**
98	* Get the packed alternative form of the given sample format.
99	*
100	* If the passed sample_fmt is already in packed format, the format returned is
101	* the same as the input.
102	*
103	* @return the packed alternative form of the given sample format or
104	AV_SAMPLE_FMT_NONE on error.
105	*/
106	enum AVSampleFormat av_get_packed_sample_fmt(enum AVSampleFormat sample_fmt);
107
108	/**
109	* Get the planar alternative form of the given sample format.
110	*
111	* If the passed sample_fmt is already in planar format, the format returned is
112	* the same as the input.
113	*
114	* @return the planar alternative form of the given sample format or
115	AV_SAMPLE_FMT_NONE on error.
116	*/
117	enum AVSampleFormat av_get_planar_sample_fmt(enum AVSampleFormat sample_fmt);
118
119	/**
120	* Generate a string corresponding to the sample format with
121	* sample_fmt, or a header if sample_fmt is negative.
122	*
123	* @param buf the buffer where to write the string
124	* @param buf_size the size of buf
125	* @param sample_fmt the number of the sample format to print the
126	* corresponding info string, or a negative value to print the
127	* corresponding header.
128	* @return the pointer to the filled buffer or NULL if sample_fmt is
129	* unknown or in case of other errors
130	*/
131	char *av_get_sample_fmt_string(char *buf, int buf_size, enum AVSampleFormat sample_fmt);
132
133	/**
134	* Return number of bytes per sample.
135	*
136	* @param sample_fmt the sample format
137	* @return number of bytes per sample or zero if unknown for the given
138	* sample format
139	*/
140	int av_get_bytes_per_sample(enum AVSampleFormat sample_fmt);
141
142	/**
143	* Check if the sample format is planar.
144	*
145	* @param sample_fmt the sample format to inspect
146	* @return 1 if the sample format is planar, 0 if it is interleaved
147	*/
148	int av_sample_fmt_is_planar(enum AVSampleFormat sample_fmt);
149
150	/**
151	* Get the required buffer size for the given audio parameters.
152	*
153	* @param[out] linesize calculated linesize, may be NULL
154	* @param nb_channels the number of channels
155	* @param nb_samples the number of samples in a single channel
156	* @param sample_fmt the sample format
157	* @param align buffer size alignment (0 = default, 1 = no alignment)
158	* @return required buffer size, or negative error code on failure
159	*/
160	int av_samples_get_buffer_size(int *linesize, int nb_channels, int nb_samples,
161	enum AVSampleFormat sample_fmt, int align);
162
163	/**
164	* @}
165	*
166	* @defgroup lavu_sampmanip Samples manipulation
167	*
168	* Functions that manipulate audio samples
169	* @{
170	*/
171
172	/**
173	* Fill plane data pointers and linesize for samples with sample
174	* format sample_fmt.
175	*
176	* The audio_data array is filled with the pointers to the samples data planes:
177	* for planar, set the start point of each channel's data within the buffer,
178	* for packed, set the start point of the entire buffer only.
179	*
180	* The value pointed to by linesize is set to the aligned size of each
181	* channel's data buffer for planar layout, or to the aligned size of the
182	* buffer for all channels for packed layout.
183	*
184	* The buffer in buf must be big enough to contain all the samples
185	* (use av_samples_get_buffer_size() to compute its minimum size),
186	* otherwise the audio_data pointers will point to invalid data.
187	*
188	* @see enum AVSampleFormat
189	* The documentation for AVSampleFormat describes the data layout.
190	*
191	* @param[out] audio_data array to be filled with the pointer for each channel
192	* @param[out] linesize calculated linesize, may be NULL
193	* @param buf the pointer to a buffer containing the samples
194	* @param nb_channels the number of channels
195	* @param nb_samples the number of samples in a single channel
196	* @param sample_fmt the sample format
197	* @param align buffer size alignment (0 = default, 1 = no alignment)
198	* @return >=0 on success or a negative error code on failure
199	* @todo return minimum size in bytes required for the buffer in case
200	* of success at the next bump
201	*/
202	int av_samples_fill_arrays(uint8_t **audio_data, int *linesize,
203	const uint8_t *buf,
204	int nb_channels, int nb_samples,
205	enum AVSampleFormat sample_fmt, int align);
206
207	/**
208	* Allocate a samples buffer for nb_samples samples, and fill data pointers and
209	* linesize accordingly.
210	* The allocated samples buffer can be freed by using av_freep(&audio_data[0])
211	* Allocated data will be initialized to silence.
212	*
213	* @see enum AVSampleFormat
214	* The documentation for AVSampleFormat describes the data layout.
215	*
216	* @param[out] audio_data array to be filled with the pointer for each channel
217	* @param[out] linesize aligned size for audio buffer(s), may be NULL
218	* @param nb_channels number of audio channels
219	* @param nb_samples number of samples per channel
220	* @param align buffer size alignment (0 = default, 1 = no alignment)
221	* @return >=0 on success or a negative error code on failure
222	* @todo return the size of the allocated buffer in case of success at the next bump
223	* @see av_samples_fill_arrays()
224	* @see av_samples_alloc_array_and_samples()
225	*/
226	int av_samples_alloc(uint8_t **audio_data, int *linesize, int nb_channels,
227	int nb_samples, enum AVSampleFormat sample_fmt, int align);
228
229	/**
230	* Allocate a data pointers array, samples buffer for nb_samples
231	* samples, and fill data pointers and linesize accordingly.
232	*
233	* This is the same as av_samples_alloc(), but also allocates the data
234	* pointers array.
235	*
236	* @see av_samples_alloc()
237	*/
238	int av_samples_alloc_array_and_samples(uint8_t ***audio_data, int *linesize, int nb_channels,
239	int nb_samples, enum AVSampleFormat sample_fmt, int align);
240
241	/**
242	* Copy samples from src to dst.
243	*
244	* @param dst destination array of pointers to data planes
245	* @param src source array of pointers to data planes
246	* @param dst_offset offset in samples at which the data will be written to dst
247	* @param src_offset offset in samples at which the data will be read from src
248	* @param nb_samples number of samples to be copied
249	* @param nb_channels number of audio channels
250	* @param sample_fmt audio sample format
251	*/
252	int av_samples_copy(uint8_t **dst, uint8_t * const *src, int dst_offset,
253	int src_offset, int nb_samples, int nb_channels,
254	enum AVSampleFormat sample_fmt);
255
256	/**
257	* Fill an audio buffer with silence.
258	*
259	* @param audio_data array of pointers to data planes
260	* @param offset offset in samples at which to start filling
261	* @param nb_samples number of samples to fill
262	* @param nb_channels number of audio channels
263	* @param sample_fmt audio sample format
264	*/
265	int av_samples_set_silence(uint8_t **audio_data, int offset, int nb_samples,
266	int nb_channels, enum AVSampleFormat sample_fmt);
267
268	/**
269	* @}
270	* @}
271	*/
272	#endif /* AVUTIL_SAMPLEFMT_H */
273