samplefmt.h (10298B)
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 39 * signed 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 72 ///< dynamically 73 }; 74 75 /** 76 * Return the name of sample_fmt, or NULL if sample_fmt is not 77 * recognized. 78 */ 79 const char* av_get_sample_fmt_name(enum AVSampleFormat sample_fmt); 80 81 /** 82 * Return a sample format corresponding to name, or AV_SAMPLE_FMT_NONE 83 * on error. 84 */ 85 enum AVSampleFormat av_get_sample_fmt(const char* name); 86 87 /** 88 * Return the planar<->packed alternative form of the given sample format, or 89 * AV_SAMPLE_FMT_NONE on error. If the passed sample_fmt is already in the 90 * requested planar/packed format, the format returned is the same as the 91 * input. 92 */ 93 enum AVSampleFormat av_get_alt_sample_fmt(enum AVSampleFormat sample_fmt, 94 int planar); 95 96 /** 97 * Get the packed alternative form of the given sample format. 98 * 99 * If the passed sample_fmt is already in packed format, the format returned is 100 * the same as the input. 101 * 102 * @return the packed alternative form of the given sample format or 103 AV_SAMPLE_FMT_NONE on error. 104 */ 105 enum AVSampleFormat av_get_packed_sample_fmt(enum AVSampleFormat sample_fmt); 106 107 /** 108 * Get the planar alternative form of the given sample format. 109 * 110 * If the passed sample_fmt is already in planar format, the format returned is 111 * the same as the input. 112 * 113 * @return the planar alternative form of the given sample format or 114 AV_SAMPLE_FMT_NONE on error. 115 */ 116 enum AVSampleFormat av_get_planar_sample_fmt(enum AVSampleFormat sample_fmt); 117 118 /** 119 * Generate a string corresponding to the sample format with 120 * sample_fmt, or a header if sample_fmt is negative. 121 * 122 * @param buf the buffer where to write the string 123 * @param buf_size the size of buf 124 * @param sample_fmt the number of the sample format to print the 125 * corresponding info string, or a negative value to print the 126 * corresponding header. 127 * @return the pointer to the filled buffer or NULL if sample_fmt is 128 * unknown or in case of other errors 129 */ 130 char* av_get_sample_fmt_string(char* buf, int buf_size, 131 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 minimum size in bytes required for the buffer on 199 * success, or a negative error code on failure 200 */ 201 int av_samples_fill_arrays(uint8_t** audio_data, int* linesize, 202 const uint8_t* buf, int nb_channels, int nb_samples, 203 enum AVSampleFormat sample_fmt, int align); 204 205 /** 206 * Allocate a samples buffer for nb_samples samples, and fill data pointers and 207 * linesize accordingly. 208 * The allocated samples buffer can be freed by using av_freep(&audio_data[0]) 209 * Allocated data will be initialized to silence. 210 * 211 * @see enum AVSampleFormat 212 * The documentation for AVSampleFormat describes the data layout. 213 * 214 * @param[out] audio_data array to be filled with the pointer for each channel 215 * @param[out] linesize aligned size for audio buffer(s), may be NULL 216 * @param nb_channels number of audio channels 217 * @param nb_samples number of samples per channel 218 * @param sample_fmt the sample format 219 * @param align buffer size alignment (0 = default, 1 = no alignment) 220 * @return >=0 on success or a negative error code on failure 221 * @todo return the size of the allocated buffer in case of success at the next 222 * 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, 239 int nb_channels, int nb_samples, 240 enum AVSampleFormat sample_fmt, 241 int align); 242 243 /** 244 * Copy samples from src to dst. 245 * 246 * @param dst destination array of pointers to data planes 247 * @param src source array of pointers to data planes 248 * @param dst_offset offset in samples at which the data will be written to dst 249 * @param src_offset offset in samples at which the data will be read from src 250 * @param nb_samples number of samples to be copied 251 * @param nb_channels number of audio channels 252 * @param sample_fmt audio sample format 253 */ 254 int av_samples_copy(uint8_t** dst, uint8_t* const* src, int dst_offset, 255 int src_offset, int nb_samples, int nb_channels, 256 enum AVSampleFormat sample_fmt); 257 258 /** 259 * Fill an audio buffer with silence. 260 * 261 * @param audio_data array of pointers to data planes 262 * @param offset offset in samples at which to start filling 263 * @param nb_samples number of samples to fill 264 * @param nb_channels number of audio channels 265 * @param sample_fmt audio sample format 266 */ 267 int av_samples_set_silence(uint8_t** audio_data, int offset, int nb_samples, 268 int nb_channels, enum AVSampleFormat sample_fmt); 269 270 /** 271 * @} 272 * @} 273 */ 274 #endif /* AVUTIL_SAMPLEFMT_H */