#include "libavutil/audioconvert.h"
#include "libavutil/avutil.h"
#include "libavutil/dict.h"
#include "libavutil/log.h"
#include "libavresample/version.h"
Go to the source code of this file.
Defines | |
| #define | AVRESAMPLE_MAX_CHANNELS 32 |
Typedefs | |
| typedef struct AVAudioResampleContext | AVAudioResampleContext |
Enumerations | |
| enum | AVMixCoeffType { AV_MIX_COEFF_TYPE_Q8, AV_MIX_COEFF_TYPE_Q15, AV_MIX_COEFF_TYPE_FLT, AV_MIX_COEFF_TYPE_NB } |
| Mixing Coefficient Types. More... | |
| enum | AVResampleFilterType { AV_RESAMPLE_FILTER_TYPE_CUBIC, AV_RESAMPLE_FILTER_TYPE_BLACKMAN_NUTTALL, AV_RESAMPLE_FILTER_TYPE_KAISER } |
| Resampling Filter Types. More... | |
Functions | |
| unsigned | avresample_version (void) |
| Return the LIBAVRESAMPLE_VERSION_INT constant. | |
| const char * | avresample_configuration (void) |
| Return the libavresample build-time configuration. | |
| const char * | avresample_license (void) |
| Return the libavresample license. | |
| const AVClass * | avresample_get_class (void) |
| Get the AVClass for AVAudioResampleContext. | |
| AVAudioResampleContext * | avresample_alloc_context (void) |
| Allocate AVAudioResampleContext and set options. | |
| int | avresample_open (AVAudioResampleContext *avr) |
| Initialize AVAudioResampleContext. | |
| void | avresample_close (AVAudioResampleContext *avr) |
| Close AVAudioResampleContext. | |
| void | avresample_free (AVAudioResampleContext **avr) |
| Free AVAudioResampleContext and associated AVOption values. | |
| int | avresample_build_matrix (uint64_t in_layout, uint64_t out_layout, double center_mix_level, double surround_mix_level, double lfe_mix_level, int normalize, double *matrix, int stride, enum AVMatrixEncoding matrix_encoding) |
| Generate a channel mixing matrix. | |
| int | avresample_get_matrix (AVAudioResampleContext *avr, double *matrix, int stride) |
| Get the current channel mixing matrix. | |
| int | avresample_set_matrix (AVAudioResampleContext *avr, const double *matrix, int stride) |
| Set channel mixing matrix. | |
| int | avresample_set_compensation (AVAudioResampleContext *avr, int sample_delta, int compensation_distance) |
| Set compensation for resampling. | |
| int | avresample_convert (AVAudioResampleContext *avr, void **output, int out_plane_size, int out_samples, void **input, int in_plane_size, int in_samples) |
| Convert input samples and write them to the output FIFO. | |
| int | avresample_get_delay (AVAudioResampleContext *avr) |
| Return the number of samples currently in the resampling delay buffer. | |
| int | avresample_available (AVAudioResampleContext *avr) |
| Return the number of available samples in the output FIFO. | |
| int | avresample_read (AVAudioResampleContext *avr, void **output, int nb_samples) |
| Read samples from the output FIFO. | |
Definition in file avresample.h.
| #define AVRESAMPLE_MAX_CHANNELS 32 |
Definition at line 36 of file avresample.h.
Referenced by audiogen(), avresample_build_matrix(), avresample_get_matrix(), avresample_open(), avresample_set_compensation(), avresample_set_matrix(), ff_audio_data_add_to_fifo(), ff_audio_data_alloc(), ff_audio_data_init(), ff_audio_data_realloc(), ff_audio_data_set_channels(), and main().
| typedef struct AVAudioResampleContext AVAudioResampleContext |
Definition at line 38 of file avresample.h.
| enum AVMixCoeffType |
Mixing Coefficient Types.
| AV_MIX_COEFF_TYPE_Q8 | |
| AV_MIX_COEFF_TYPE_Q15 | 16-bit 8.8 fixed-point |
| AV_MIX_COEFF_TYPE_FLT | 32-bit 17.15 fixed-point |
| AV_MIX_COEFF_TYPE_NB | floating-point |
Definition at line 41 of file avresample.h.
| enum AVResampleFilterType |
Resampling Filter Types.
| AV_RESAMPLE_FILTER_TYPE_CUBIC | Cubic. |
| AV_RESAMPLE_FILTER_TYPE_BLACKMAN_NUTTALL | Blackman Nuttall Windowed Sinc. |
| AV_RESAMPLE_FILTER_TYPE_KAISER | Kaiser Windowed Sinc. |
Definition at line 49 of file avresample.h.
| AVAudioResampleContext* avresample_alloc_context | ( | void | ) |
Allocate AVAudioResampleContext and set options.
Definition at line 76 of file options.c.
Referenced by config_output(), config_props(), and main().
| int avresample_available | ( | AVAudioResampleContext * | avr | ) |
Return the number of available samples in the output FIFO.
During conversion, if the user does not specify an output buffer or specifies an output buffer that is smaller than what is needed, remaining samples that are not written to the output are stored to an internal FIFO buffer. The samples in the FIFO can be read with avresample_read() or avresample_convert().
| avr | audio resample context |
Definition at line 408 of file utils.c.
Referenced by filter_samples(), get_delay(), and main().
| int avresample_build_matrix | ( | uint64_t | in_layout, | |
| uint64_t | out_layout, | |||
| double | center_mix_level, | |||
| double | surround_mix_level, | |||
| double | lfe_mix_level, | |||
| int | normalize, | |||
| double * | matrix, | |||
| int | stride, | |||
| enum AVMatrixEncoding | matrix_encoding | |||
| ) |
Generate a channel mixing matrix.
This function is the one used internally by libavresample for building the default mixing matrix. It is made public just as a utility function for building custom matrices.
| in_layout | input channel layout | |
| out_layout | output channel layout | |
| center_mix_level | mix level for the center channel | |
| surround_mix_level | mix level for the surround channel(s) | |
| lfe_mix_level | mix level for the low-frequency effects channel | |
| normalize | if 1, coefficients will be normalized to prevent overflow. if 0, coefficients will not be normalized. | |
| [out] | matrix | mixing coefficients; matrix[i + stride * o] is the weight of input channel i in output channel o. |
| stride | distance between adjacent input channels in the matrix array | |
| matrix_encoding | matrixed stereo downmix mode (e.g. dplii) |
Definition at line 87 of file audio_mix_matrix.c.
Referenced by ff_audio_mix_init().
| void avresample_close | ( | AVAudioResampleContext * | avr | ) |
Close AVAudioResampleContext.
This closes the context, but it does not change the parameters. The context can be reopened with avresample_open(). It does, however, clear the output FIFO and any remaining leftover samples in the resampling delay buffer. If there was a custom matrix being used, that is also cleared.
| avr | audio resample context |
Definition at line 184 of file utils.c.
Referenced by avresample_free(), avresample_open(), avresample_set_compensation(), config_output(), main(), and uninit().
| const char* avresample_configuration | ( | void | ) |
| int avresample_convert | ( | AVAudioResampleContext * | avr, | |
| void ** | output, | |||
| int | out_plane_size, | |||
| int | out_samples, | |||
| void ** | input, | |||
| int | in_plane_size, | |||
| int | in_samples | |||
| ) |
Convert input samples and write them to the output FIFO.
The output data can be NULL or have fewer allocated samples than required. In this case, any remaining samples not written to the output will be added to an internal FIFO buffer, to be returned at the next call to this function or to avresample_read().
If converting sample rate, there may be data remaining in the internal resampling delay buffer. avresample_get_delay() tells the number of remaining samples. To get this data as output, call avresample_convert() with NULL input.
At the end of the conversion process, there may be data remaining in the internal FIFO buffer. avresample_available() tells the number of remaining samples. To get this data as output, either call avresample_convert() with NULL input or call avresample_read().
| avr | audio resample context | |
| output | output data pointers | |
| out_plane_size | output plane size, in bytes. This can be 0 if unknown, but that will lead to optimized functions not being used directly on the output, which could slow down some conversions. | |
| out_samples | maximum number of samples that the output buffer can hold | |
| input | input data pointers | |
| in_plane_size | input plane size, in bytes This can be 0 if unknown, but that will lead to optimized functions not being used directly on the input, which could slow down some conversions. | |
| in_samples | number of input samples to convert |
Definition at line 249 of file utils.c.
Referenced by filter_samples(), main(), request_frame(), and write_to_fifo().
| void avresample_free | ( | AVAudioResampleContext ** | avr | ) |
Free AVAudioResampleContext and associated AVOption values.
This also calls avresample_close() before freeing.
| avr | audio resample context |
Definition at line 198 of file utils.c.
Referenced by config_output(), main(), and uninit().
| const AVClass* avresample_get_class | ( | void | ) |
Get the AVClass for AVAudioResampleContext.
Can be used in combination with AV_OPT_SEARCH_FAKE_OBJ for examining options without allocating a context.
| int avresample_get_delay | ( | AVAudioResampleContext * | avr | ) |
Return the number of samples currently in the resampling delay buffer.
When resampling, there may be a delay between the input and output. Any unconverted samples in each call are stored internally in a delay buffer. This function allows the user to determine the current number of samples in the delay buffer, which can be useful for synchronization.
| avr | audio resample context |
Definition at line 452 of file resample.c.
Referenced by filter_samples(), get_delay(), main(), and request_frame().
| int avresample_get_matrix | ( | AVAudioResampleContext * | avr, | |
| double * | matrix, | |||
| int | stride | |||
| ) |
Get the current channel mixing matrix.
| avr | audio resample context | |
| matrix | mixing coefficients; matrix[i + stride * o] is the weight of input channel i in output channel o. | |
| stride | distance between adjacent input channels in the matrix array |
Definition at line 291 of file audio_mix_matrix.c.
Referenced by avresample_set_compensation().
| const char* avresample_license | ( | void | ) |
| int avresample_open | ( | AVAudioResampleContext * | avr | ) |
Initialize AVAudioResampleContext.
| avr | audio resample context |
Definition at line 32 of file utils.c.
Referenced by avresample_set_compensation(), config_output(), config_props(), and main().
| int avresample_read | ( | AVAudioResampleContext * | avr, | |
| void ** | output, | |||
| int | nb_samples | |||
| ) |
Read samples from the output FIFO.
During conversion, if the user does not specify an output buffer or specifies an output buffer that is smaller than what is needed, remaining samples that are not written to the output are stored to an internal FIFO buffer. This function can be used to read samples from that internal FIFO.
| avr | audio resample context | |
| output | output data pointers. May be NULL, in which case nb_samples of data is discarded from output FIFO. | |
| nb_samples | number of samples to read from the FIFO |
Definition at line 413 of file utils.c.
Referenced by filter_samples().
| int avresample_set_compensation | ( | AVAudioResampleContext * | avr, | |
| int | sample_delta, | |||
| int | compensation_distance | |||
| ) |
Set compensation for resampling.
This can be called anytime after avresample_open(). If resampling was not being done previously, the AVAudioResampleContext is closed and reopened with resampling enabled. In this case, any samples remaining in the output FIFO and the current channel mixing matrix will be restored after reopening the context.
| avr | audio resample context | |
| sample_delta | compensation delta, in samples | |
| compensation_distance | compensation distance, in samples |
Definition at line 246 of file resample.c.
Referenced by filter_samples().
| int avresample_set_matrix | ( | AVAudioResampleContext * | avr, | |
| const double * | matrix, | |||
| int | stride | |||
| ) |
Set channel mixing matrix.
Allows for setting a custom mixing matrix, overriding the default matrix generated internally during avresample_open(). This function can be called anytime on an allocated context, either before or after calling avresample_open(). avresample_convert() always uses the current matrix. Calling avresample_close() on the context will clear the current matrix.
| avr | audio resample context | |
| matrix | mixing coefficients; matrix[i + stride * o] is the weight of input channel i in output channel o. | |
| stride | distance between adjacent input channels in the matrix array |
Definition at line 341 of file audio_mix_matrix.c.
Referenced by avresample_set_compensation(), and ff_audio_mix_init().
| unsigned avresample_version | ( | void | ) |
1.5.8