samplefmt: add av_get_bytes_per_sample()

Deprecate av_get_bits_per_sample_fmt(), which was a misnamed function.

For the moment we don't have sample formats with a non-integer number
of bytes, in that case we may need to create a new
av_get_bits_per_sample() function. In the meanwhile we prefer to adopt
this variant, since avoids divisions by 8 all over the place.

doc/APIchanges

@@ -13,6 +13,10 @@ libavutil:   2011-04-18
 
 API changes, most recent first:
 
+2011-06-07 - xxxxxxx - lavu 51.4.0 - av_get_bytes_per_sample()
+  Add av_get_bytes_per_sample() in libavutil/samplefmt.h.
+  Deprecate av_get_bits_per_sample_fmt().
+
 2011-06-xx - xxxxxxx - lavu 51.3.0 - opt.h
   Add av_opt_free convenience function.
 

libavutil/avutil.h

@@ -40,7 +40,7 @@
 #define AV_VERSION(a, b, c) AV_VERSION_DOT(a, b, c)
 
 #define LIBAVUTIL_VERSION_MAJOR 51
-#define LIBAVUTIL_VERSION_MINOR  3
+#define LIBAVUTIL_VERSION_MINOR  4
 #define LIBAVUTIL_VERSION_MICRO  0
 
 #define LIBAVUTIL_VERSION_INT   AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \
@@ -57,6 +57,9 @@
  * Those FF_API_* defines are not part of public API.
  * They may change, break or disappear at any time.
  */
+#ifndef FF_API_GET_BITS_PER_SAMPLE_FMT
+#define FF_API_GET_BITS_PER_SAMPLE_FMT (LIBAVUTIL_VERSION_MAJOR < 52)
+#endif
 
 /**
  * Return the LIBAVUTIL_VERSION_INT constant.

libavutil/samplefmt.c

@@ -66,8 +66,16 @@ char *av_get_sample_fmt_string (char *buf, int buf_size, enum AVSampleFormat sam
     return buf;
 }
 
+int av_get_bytes_per_sample(enum AVSampleFormat sample_fmt)
+{
+     return sample_fmt < 0 || sample_fmt >= AV_SAMPLE_FMT_NB ?
+        0 : sample_fmt_info[sample_fmt].bits >> 3;
+}
+
+#if FF_API_GET_BITS_PER_SAMPLE_FMT
 int av_get_bits_per_sample_fmt(enum AVSampleFormat sample_fmt)
 {
     return sample_fmt < 0 || sample_fmt >= AV_SAMPLE_FMT_NB ?
         0 : sample_fmt_info[sample_fmt].bits;
 }
+#endif

libavutil/samplefmt.h

@@ -19,6 +19,8 @@
 #ifndef AVUTIL_SAMPLEFMT_H
 #define AVUTIL_SAMPLEFMT_H
 
+#include "avutil.h"
+
 /**
  * all in native-endian format
  */
@@ -58,13 +60,21 @@ enum AVSampleFormat av_get_sample_fmt(const char *name);
  */
 char *av_get_sample_fmt_string(char *buf, int buf_size, enum AVSampleFormat sample_fmt);
 
+#if FF_API_GET_BITS_PER_SAMPLE_FMT
+/**
+ * @deprecated Use av_get_bytes_per_sample() instead.
+ */
+attribute_deprecated
+int av_get_bits_per_sample_fmt(enum AVSampleFormat sample_fmt);
+#endif
+
 /**
- * Return sample format bits per sample.
+ * Return number of bytes per sample.
  *
  * @param sample_fmt the sample format
- * @return number of bits per sample or zero if unknown for the given
+ * @return number of bytes per sample or zero if unknown for the given
  * sample format
  */
-int av_get_bits_per_sample_fmt(enum AVSampleFormat sample_fmt);
+int av_get_bytes_per_sample(enum AVSampleFormat sample_fmt);
 
 #endif /* AVUTIL_SAMPLEFMT_H */