[FFmpeg-devel] [PATCH] swresample: Add AVFrame based API

[Timothy Gu]

On Aug 10, 2014 4:49 PM, "Michael Niedermayer" <michaelni at gmx.at> wrote:
>
> From: Luca Barbato <lu_zero at gentoo.org>
>
> TODO:bump
>
> Signed-off-by: Michael Niedermayer <michaelni at gmx.at>
> ---
>  libswresample/Makefile           |    1 +
>  libswresample/swresample.h       |   61 +++++++++++++++
>  libswresample/swresample_frame.c |  158
++++++++++++++++++++++++++++++++++++++
>  3 files changed, 220 insertions(+)
>  create mode 100644 libswresample/swresample_frame.c
>
> diff --git a/libswresample/Makefile b/libswresample/Makefile
> index 75c6535..120ee33 100644
> --- a/libswresample/Makefile
> +++ b/libswresample/Makefile
> @@ -13,6 +13,7 @@ OBJS = audioconvert.o                        \
>         resample.o                            \
>         resample_dsp.o                        \
>         swresample.o                          \
> +       swresample_frame.o                    \
>
>  OBJS-$(CONFIG_LIBSOXR) += soxr_resample.o
>  OBJS-$(CONFIG_SHARED)  += log2_tab.o
> diff --git a/libswresample/swresample.h b/libswresample/swresample.h
> index 4b8b045..687891b 100644
> --- a/libswresample/swresample.h
> +++ b/libswresample/swresample.h
> @@ -121,6 +121,7 @@
>   */
>
>  #include <stdint.h>
> +#include "libavutil/frame.h"
>  #include "libavutil/samplefmt.h"
>
>  #include "libswresample/version.h"
> @@ -467,6 +468,66 @@ const char *swresample_license(void);
>
>  /**
>   * @}
> + *
> + * @name AVFrame based API
> + * @{
> + */
> +
> +/**
> + * Convert the samples in the input AVFrame and write them to the output
AVFrame.
> + *
> + * Input and output AVFrames must have channel_layout, sample_rate and
format set.
> + *
> + * If the output AVFrame does not have the data pointers allocated the
nb_samples
> + * field will be set using av_frame_get_buffer()
> + * is called to allocate the frame.
> + *
> + * The output AVFrame 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 swr_convert() or to swr_convert_frame().

at the next call to this function or to swr_convert().

> + *
> + * If converting sample rate, there may be data remaining in the internal
> + * resampling delay buffer. swr_get_delay() tells the number of
> + * remaining samples. To get this data as output, call this function or
> + * swr_convert() with NULL input.
> + *
> + * If the SwrContext configuration does not match the output and
> + * input AVFrame settings the conversion does not take place and
depending on
> + * which AVFrame is not matching AVERROR_OUTPUT_CHANGED,
AVERROR_INPUT_CHANGED

> + * or AVERROR_OUTPUT_CHANGED|AVERROR_INPUT_CHANGED is returned.

or the result of a bitwise-OR of them is returned.

> + *
> + * @see swr_delay()
> + * @see swr_convert()
> + * @see swr_get_delay()
> + *
> + * @param swr             audio resample context
> + * @param output          output AVFrame
> + * @param input           input AVFrame
> + * @return                0 on success, AVERROR on failure or nonmatching
> + *                        configuration.
> + */
> +int swr_convert_frame(SwrContext *swr,
> +                      AVFrame *output, AVFrame *input);
> +
> +/**
> + * Configure or reconfigure the SwrContext using the information
> + * provided by the AVFrames.
> + *

> + * The original resampling context is reset even on failure.
> + * The function calls swr_close() internally if the context is open.

swr_close does nothing. Is it appropriate to list it here? Also, I don't
think SwrContext has a concept of open or close.

> + *
> + * @see swr_close();
> + *
> + * @param swr             audio resample context
> + * @param output          output AVFrame
> + * @param input           input AVFrame
> + * @return                0 on success, AVERROR on failure.
> + */
> +int swr_config_by_frames(SwrContext *swr, AVFrame *out, AVFrame *in);
> +
> +/**
> + * @}
>   * @}
>   */

[...]

Timothy