samplefmt.h (10318B)
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 */