Changeset e6bba8f in mainline

Timestamp:

2012-07-17T08:56:21Z (12 years ago)

Author:

Jan Vesely <jano.vesely@…>

Branches:

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

Children:

cd8f19d

Parents:

ea6c838

Message:

libpcm: Add function to generate normalized silence.

Location:

uspace/lib/pcm

Files:

• include/pcm/format.h (modified) (1 diff)
• src/format.c (modified) (1 diff)

uspace/lib/pcm/include/pcm/format.h

@@ -69 +69 @@
         return pcm_format_same(f, &AUDIO_FORMAT_ANY);
 }
+void pcm_format_silence(void *dst, size_t size, const pcm_format_t *f);
 int pcm_format_convert_and_mix(void *dst, size_t dst_size, const void *src,
     size_t src_size, const pcm_format_t *sf, const pcm_format_t *df);

uspace/lib/pcm/src/format.c

@@ -86 +86 @@
             a->channels == b->channels &&
             a->sample_format == b->sample_format;
+}
+
+void pcm_format_silence(void *dst, size_t size, const pcm_format_t *f)
+{
+#define SET_NULL(type, endian, nullv) \
+do { \
+        type *buffer = dst; \
+        const size_t sample_count = size / sizeof(type); \
+        for (unsigned i = 0; i < sample_count; ++i) { \
+                buffer[i] = to((type)nullv, type, endian); \
+        } \
+} while (0)
+
+        switch (f->sample_format) {
+        case PCM_SAMPLE_UINT8:
+                SET_NULL(uint8_t, le, INT8_MIN); break;
+        case PCM_SAMPLE_SINT8:
+                SET_NULL(int8_t, le, 0); break;
+        case PCM_SAMPLE_UINT16_LE:
+                SET_NULL(uint16_t, le, INT16_MIN); break;
+        case PCM_SAMPLE_SINT16_LE:
+                SET_NULL(int16_t, le, 0); break;
+        case PCM_SAMPLE_UINT16_BE:
+                SET_NULL(uint16_t, be, INT16_MIN); break;
+        case PCM_SAMPLE_SINT16_BE:
+                SET_NULL(int16_t, be, 0); break;
+        case PCM_SAMPLE_UINT32_LE:
+                SET_NULL(uint32_t, le, INT32_MIN); break;
+        case PCM_SAMPLE_SINT32_LE:
+                SET_NULL(int32_t, le, 0); break;
+        case PCM_SAMPLE_UINT32_BE:
+                SET_NULL(uint32_t, be, INT32_MIN); break;
+        case PCM_SAMPLE_SINT32_BE:
+                SET_NULL(int32_t, le, 0); break;
+        case PCM_SAMPLE_UINT24_32_LE:
+        case PCM_SAMPLE_SINT24_32_LE:
+        case PCM_SAMPLE_UINT24_32_BE:
+        case PCM_SAMPLE_SINT24_32_BE:
+        case PCM_SAMPLE_UINT24_LE:
+        case PCM_SAMPLE_SINT24_LE:
+        case PCM_SAMPLE_UINT24_BE:
+        case PCM_SAMPLE_SINT24_BE:
+        case PCM_SAMPLE_FLOAT32:
+        default: ;
+        }
+#undef SET_NULL
 }