samplefmt.h (10301B)
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 /** 25 * @addtogroup lavu_audio 26 * @{ 27 * 28 * @defgroup lavu_sampfmts Audio sample formats 29 * 30 * Audio sample format enumeration and related convenience functions. 31 * @{ 32 */ 33 34 /** 35 * Audio sample formats 36 * 37 * - The data described by the sample format is always in native-endian order. 38 * Sample values can be expressed by native C types, hence the lack of a signed 39 * 24-bit sample format even though it is a common raw audio data format. 40 * 41 * - The floating-point formats are based on full volume being in the range 42 * [-1.0, 1.0]. Any values outside this range are beyond full volume level. 43 * 44 * - The data layout as used in av_samples_fill_arrays() and elsewhere in FFmpeg 45 * (such as AVFrame in libavcodec) is as follows: 46 * 47 * @par 48 * For planar sample formats, each audio channel is in a separate data plane, 49 * and linesize is the buffer size, in bytes, for a single plane. All data 50 * planes must be the same size. For packed sample formats, only the first data 51 * plane is used, and samples for each channel are interleaved. In this case, 52 * linesize is the buffer size, in bytes, for the 1 plane. 53 * 54 */ 55 enum AVSampleFormat { 56 AV_SAMPLE_FMT_NONE = -1, 57 AV_SAMPLE_FMT_U8, ///< unsigned 8 bits 58 AV_SAMPLE_FMT_S16, ///< signed 16 bits 59 AV_SAMPLE_FMT_S32, ///< signed 32 bits 60 AV_SAMPLE_FMT_FLT, ///< float 61 AV_SAMPLE_FMT_DBL, ///< double 62 63 AV_SAMPLE_FMT_U8P, ///< unsigned 8 bits, planar 64 AV_SAMPLE_FMT_S16P, ///< signed 16 bits, planar 65 AV_SAMPLE_FMT_S32P, ///< signed 32 bits, planar 66 AV_SAMPLE_FMT_FLTP, ///< float, planar 67 AV_SAMPLE_FMT_DBLP, ///< double, planar 68 AV_SAMPLE_FMT_S64, ///< signed 64 bits 69 AV_SAMPLE_FMT_S64P, ///< signed 64 bits, planar 70 71 AV_SAMPLE_FMT_NB ///< Number of sample formats. DO NOT USE if linking dynamically 72 }; 73 74 /** 75 * Return the name of sample_fmt, or NULL if sample_fmt is not 76 * recognized. 77 */ 78 const char *av_get_sample_fmt_name(enum AVSampleFormat sample_fmt); 79 80 /** 81 * Return a sample format corresponding to name, or AV_SAMPLE_FMT_NONE 82 * on error. 83 */ 84 enum AVSampleFormat av_get_sample_fmt(const char *name); 85 86 /** 87 * Return the planar<->packed alternative form of the given sample format, or 88 * AV_SAMPLE_FMT_NONE on error. If the passed sample_fmt is already in the 89 * requested planar/packed format, the format returned is the same as the 90 * input. 91 */ 92 enum AVSampleFormat av_get_alt_sample_fmt(enum AVSampleFormat sample_fmt, int planar); 93 94 /** 95 * Get the packed alternative form of the given sample format. 96 * 97 * If the passed sample_fmt is already in packed format, the format returned is 98 * the same as the input. 99 * 100 * @return the packed alternative form of the given sample format or 101 AV_SAMPLE_FMT_NONE on error. 102 */ 103 enum AVSampleFormat av_get_packed_sample_fmt(enum AVSampleFormat sample_fmt); 104 105 /** 106 * Get the planar alternative form of the given sample format. 107 * 108 * If the passed sample_fmt is already in planar format, the format returned is 109 * the same as the input. 110 * 111 * @return the planar alternative form of the given sample format or 112 AV_SAMPLE_FMT_NONE on error. 113 */ 114 enum AVSampleFormat av_get_planar_sample_fmt(enum AVSampleFormat sample_fmt); 115 116 /** 117 * Generate a string corresponding to the sample format with 118 * sample_fmt, or a header if sample_fmt is negative. 119 * 120 * @param buf the buffer where to write the string 121 * @param buf_size the size of buf 122 * @param sample_fmt the number of the sample format to print the 123 * corresponding info string, or a negative value to print the 124 * corresponding header. 125 * @return the pointer to the filled buffer or NULL if sample_fmt is 126 * unknown or in case of other errors 127 */ 128 char *av_get_sample_fmt_string(char *buf, int buf_size, enum AVSampleFormat sample_fmt); 129 130 /** 131 * Return number of bytes per sample. 132 * 133 * @param sample_fmt the sample format 134 * @return number of bytes per sample or zero if unknown for the given 135 * sample format 136 */ 137 int av_get_bytes_per_sample(enum AVSampleFormat sample_fmt); 138 139 /** 140 * Check if the sample format is planar. 141 * 142 * @param sample_fmt the sample format to inspect 143 * @return 1 if the sample format is planar, 0 if it is interleaved 144 */ 145 int av_sample_fmt_is_planar(enum AVSampleFormat sample_fmt); 146 147 /** 148 * Get the required buffer size for the given audio parameters. 149 * 150 * @param[out] linesize calculated linesize, may be NULL 151 * @param nb_channels the number of channels 152 * @param nb_samples the number of samples in a single channel 153 * @param sample_fmt the sample format 154 * @param align buffer size alignment (0 = default, 1 = no alignment) 155 * @return required buffer size, or negative error code on failure 156 */ 157 int av_samples_get_buffer_size(int *linesize, int nb_channels, int nb_samples, 158 enum AVSampleFormat sample_fmt, int align); 159 160 /** 161 * @} 162 * 163 * @defgroup lavu_sampmanip Samples manipulation 164 * 165 * Functions that manipulate audio samples 166 * @{ 167 */ 168 169 /** 170 * Fill plane data pointers and linesize for samples with sample 171 * format sample_fmt. 172 * 173 * The audio_data array is filled with the pointers to the samples data planes: 174 * for planar, set the start point of each channel's data within the buffer, 175 * for packed, set the start point of the entire buffer only. 176 * 177 * The value pointed to by linesize is set to the aligned size of each 178 * channel's data buffer for planar layout, or to the aligned size of the 179 * buffer for all channels for packed layout. 180 * 181 * The buffer in buf must be big enough to contain all the samples 182 * (use av_samples_get_buffer_size() to compute its minimum size), 183 * otherwise the audio_data pointers will point to invalid data. 184 * 185 * @see enum AVSampleFormat 186 * The documentation for AVSampleFormat describes the data layout. 187 * 188 * @param[out] audio_data array to be filled with the pointer for each channel 189 * @param[out] linesize calculated linesize, may be NULL 190 * @param buf the pointer to a buffer containing the samples 191 * @param nb_channels the number of channels 192 * @param nb_samples the number of samples in a single channel 193 * @param sample_fmt the sample format 194 * @param align buffer size alignment (0 = default, 1 = no alignment) 195 * @return minimum size in bytes required for the buffer on success, 196 * or a negative error code on failure 197 */ 198 int av_samples_fill_arrays(uint8_t **audio_data, int *linesize, 199 const uint8_t *buf, 200 int nb_channels, int nb_samples, 201 enum AVSampleFormat sample_fmt, int align); 202 203 /** 204 * Allocate a samples buffer for nb_samples samples, and fill data pointers and 205 * linesize accordingly. 206 * The allocated samples buffer can be freed by using av_freep(&audio_data[0]) 207 * Allocated data will be initialized to silence. 208 * 209 * @see enum AVSampleFormat 210 * The documentation for AVSampleFormat describes the data layout. 211 * 212 * @param[out] audio_data array to be filled with the pointer for each channel 213 * @param[out] linesize aligned size for audio buffer(s), may be NULL 214 * @param nb_channels number of audio channels 215 * @param nb_samples number of samples per channel 216 * @param sample_fmt the sample format 217 * @param align buffer size alignment (0 = default, 1 = no alignment) 218 * @return >=0 on success or a negative error code on failure 219 * @todo return the size of the allocated buffer in case of success at the next bump 220 * @see av_samples_fill_arrays() 221 * @see av_samples_alloc_array_and_samples() 222 */ 223 int av_samples_alloc(uint8_t **audio_data, int *linesize, int nb_channels, 224 int nb_samples, enum AVSampleFormat sample_fmt, int align); 225 226 /** 227 * Allocate a data pointers array, samples buffer for nb_samples 228 * samples, and fill data pointers and linesize accordingly. 229 * 230 * This is the same as av_samples_alloc(), but also allocates the data 231 * pointers array. 232 * 233 * @see av_samples_alloc() 234 */ 235 int av_samples_alloc_array_and_samples(uint8_t ***audio_data, int *linesize, int nb_channels, 236 int nb_samples, enum AVSampleFormat sample_fmt, int align); 237 238 /** 239 * Copy samples from src to dst. 240 * 241 * @param dst destination array of pointers to data planes 242 * @param src source array of pointers to data planes 243 * @param dst_offset offset in samples at which the data will be written to dst 244 * @param src_offset offset in samples at which the data will be read from src 245 * @param nb_samples number of samples to be copied 246 * @param nb_channels number of audio channels 247 * @param sample_fmt audio sample format 248 */ 249 int av_samples_copy(uint8_t * const *dst, uint8_t * const *src, int dst_offset, 250 int src_offset, int nb_samples, int nb_channels, 251 enum AVSampleFormat sample_fmt); 252 253 /** 254 * Fill an audio buffer with silence. 255 * 256 * @param audio_data array of pointers to data planes 257 * @param offset offset in samples at which to start filling 258 * @param nb_samples number of samples to fill 259 * @param nb_channels number of audio channels 260 * @param sample_fmt audio sample format 261 */ 262 int av_samples_set_silence(uint8_t * const *audio_data, int offset, int nb_samples, 263 int nb_channels, enum AVSampleFormat sample_fmt); 264 265 /** 266 * @} 267 * @} 268 */ 269 #endif /* AVUTIL_SAMPLEFMT_H */