Changeset b1dfe13 in mainline for uspace/lib/pcm/include/pcm/sample_format.h

Timestamp:

2013-04-10T19:08:09Z (13 years ago)

Author:

Jan Vesely <jano.vesely@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

8a7d78cc

Parents:

a8e87da

Message:

libpcm: comments

File:

• uspace/lib/pcm/include/pcm/sample_format.h (modified) (6 diffs)

uspace/lib/pcm/include/pcm/sample_format.h

@@ -40 +40 @@
 #include <time.h>
 
+/** Known and supported PCM sample formats */
 typedef enum {
         PCM_SAMPLE_UINT8,
@@ -63 +64 @@
 } pcm_sample_format_t;
 
+/**
+ * Query if the format uses signed values.
+ * @param format PCM sample format.
+ * @return True if the format uses signed values, false otherwise.
+ */
 static inline bool pcm_sample_format_is_signed(pcm_sample_format_t format)
 {
@@ -91 +97 @@
 }
 
+/**
+ * Query byte-size of samples.
+ * @param format PCM sample format.
+ * @return Size in bytes of a single sample.
+ */
 static inline size_t pcm_sample_format_size(pcm_sample_format_t format)
 {
@@ -122 +133 @@
 }
 
+/**
+ * Query sie of the entire frame.
+ * @param channels Number of samples in every frame.
+ * @param format PCM sample format.
+ * @return Size in bytes.
+ */
 static inline size_t pcm_sample_format_frame_size(unsigned channels,
     pcm_sample_format_t format)
@@ -128 +145 @@
 }
 
+/**
+ * Count number of frames that fit into a buffer (even incomplete frames).
+ * @param size Size of the buffer.
+ * @param channels Number of samples in every frame.
+ * @param format PCM sample format.
+ * @return Number of frames (even incomplete).
+ */
 static inline size_t pcm_sample_format_size_to_frames(size_t size,
     unsigned channels, pcm_sample_format_t format)
@@ -135 +159 @@
 }
 
+/**
+ * Convert byte size to time.
+ * @param size Size of the buffer.
+ * @param sample_rate Samples per second.
+ * @param channels Number of samples in every frame.
+ * @param format PCM sample format.
+ * @return Number of useconds of audio data.
+ */
 static inline useconds_t pcm_sample_format_size_to_usec(size_t size,
     unsigned sample_rate, unsigned channels, pcm_sample_format_t format)
 {
-        const long long frames =
+        const unsigned long long frames =
             pcm_sample_format_size_to_frames(size, channels, format);
         return (frames * 1000000ULL) / sample_rate;
 }
 
+/**
+ * Get readable name of a sample format.
+ * @param format PCM sample format.
+ * @return Valid string representation.
+ */
 static inline const char * pcm_sample_format_str(pcm_sample_format_t format)
 {