@@ -18,6 +18,11 @@

  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

  */

+/**

+ * @file

+ * libswresample public header

+ */

+

 #ifndef SWR_H

 #define SWR_H

@@ -28,9 +33,9 @@

 #define LIBSWRESAMPLE_VERSION_MINOR 3

 #define LIBSWRESAMPLE_VERSION_MICRO 0

-#define SWR_CH_MAX 16

+#define SWR_CH_MAX 16   ///< Maximum number of channels

-#define SWR_FLAG_RESAMPLE 1///< Force resampling even if equal sample rate

+#define SWR_FLAG_RESAMPLE 1 ///< Force resampling even if equal sample rate

 //TODO use int resample ?

 //long term TODO can we enable this dynamically?

@@ -39,21 +44,43 @@ struct SwrContext;

 /**

  * Allocate SwrContext.

- * @see swr_init(),swr_free()

- * @return NULL on error

+ *

+ * If you use this function you will need to set the parameters (manually or

+ * with swr_alloc_set_opts()) before calling swr_init().

+ *

+ * @see swr_alloc_set_opts(), swr_init(), swr_free()

+ * @return NULL on error, allocated context otherwise

  */

 struct SwrContext *swr_alloc(void);

 /**

  * Initialize context after user parameters have been set.

- * @return negativo n error

+ *

+ * @return AVERROR error code in case of failure.

  */

 int swr_init(struct SwrContext *s);

 /**

- * Allocate SwrContext.

- * @see swr_init(),swr_free()

- * @return NULL on error

+ * Allocate SwrContext if needed and set/reset common parameters.

+ *

+ * This function does not require s to be allocated with swr_alloc(). On the

+ * other hand, swr_alloc() can use swr_alloc_set_opts() to set the parameters

+ * on the allocated context.

+ *

+ * @param s               Swr context, can be NULL

+ * @param out_ch_layout   output channel layout (AV_CH_LAYOUT_*)

+ * @param out_sample_fmt  output sample format (AV_SAMPLE_FMT_*). Use +0x100 for planar audio

+ * @param out_sample_rate output sample rate (frequency in Hz)

+ * @param in_ch_layout    input channel layout (AV_CH_LAYOUT_*)

+ * @param in_sample_fmt   input sample format (AV_SAMPLE_FMT_*). Use +0x100 for planar audio

+ * @param in_sample_rate  input sample rate (frequency in Hz)

+ * @param channel_map     customized input channel mapping (array of channel

+ *                        indexes, -1 for a muted channel), can be NULL

+ * @param log_offset      logging level offset

+ * @param log_ctx         parent logging context, can be NULL

+ *

+ * @see swr_init(), swr_free()

+ * @return NULL on error, allocated context otherwise

  */

 struct SwrContext *swr_alloc_set_opts(struct SwrContext *s,

                                       int64_t out_ch_layout, enum AVSampleFormat out_sample_fmt, int out_sample_rate,

@@ -61,22 +88,30 @@ struct SwrContext *swr_alloc_set_opts(struct SwrContext *s,

                                       const int *channel_map, int log_offset, void *log_ctx);

 /**

- * Free the given SwrContext.

- * And set the pointer to NULL

+ * Free the given SwrContext and set the pointer to NULL.

  */

 void swr_free(struct SwrContext **s);

 /**

  * Convert audio.

  *

- * in & in_count can be set to 0 to flush the last few samples out at the end.

- * @param  in_count Number of input samples available in one channel.

- * @param out_count Amount of space available for output in samples per channel.

+ * in and in_count can be set to 0 to flush the last few samples out at the

+ * end.

+ *

+ * @param s         allocated Swr context, with parameters set

+ * @param out       output buffers, only the first one need be set in case of packed audio

+ * @param out_count amount of space available for output in samples per channel

+ * @param in        input buffers, only the first one need to be set in case of packed audio

+ * @param in_count  number of input samples available in one channel

+ *

  * @return number of samples output per channel

  */

 int swr_convert(struct SwrContext *s, uint8_t *out[SWR_CH_MAX], int out_count,

                                 const uint8_t *in [SWR_CH_MAX], int in_count);

+/**

+ * Activate resampling compensation.

+ */

 void swr_compensate(struct SwrContext *s, int sample_delta, int compensation_distance);

 #endif