Adds support for 8-bit (unsigned) PCM wave files.
related-to-bug: 2382428
diff --git a/media/libstagefright/WAVExtractor.cpp b/media/libstagefright/WAVExtractor.cpp
index 959a767..da8fe79 100644
--- a/media/libstagefright/WAVExtractor.cpp
+++ b/media/libstagefright/WAVExtractor.cpp
@@ -44,7 +44,8 @@
struct WAVSource : public MediaSource {
WAVSource(
const sp<DataSource> &dataSource,
- int32_t sampleRate, int32_t numChannels,
+ const sp<MetaData> &meta,
+ int32_t bitsPerSample,
off_t offset, size_t size);
virtual status_t start(MetaData *params = NULL);
@@ -61,8 +62,10 @@
static const size_t kMaxFrameSize;
sp<DataSource> mDataSource;
+ sp<MetaData> mMeta;
int32_t mSampleRate;
int32_t mNumChannels;
+ int32_t mBitsPerSample;
off_t mOffset;
size_t mSize;
bool mStarted;
@@ -104,7 +107,8 @@
}
return new WAVSource(
- mDataSource, mSampleRate, mNumChannels, mDataOffset, mDataSize);
+ mDataSource, mTrackMeta,
+ mBitsPerSample, mDataOffset, mDataSize);
}
sp<MetaData> WAVExtractor::getTrackMetaData(
@@ -113,17 +117,7 @@
return NULL;
}
- sp<MetaData> meta = new MetaData;
- meta->setCString(kKeyMIMEType, MEDIA_MIMETYPE_AUDIO_RAW);
- meta->setInt32(kKeyChannelCount, mNumChannels);
- meta->setInt32(kKeySampleRate, mSampleRate);
-
- int64_t durationUs =
- 1000000LL * (mDataSize / (mNumChannels * 2)) / mSampleRate;
-
- meta->setInt64(kKeyDuration, durationUs);
-
- return meta;
+ return mTrackMeta;
}
status_t WAVExtractor::init() {
@@ -149,7 +143,7 @@
remainingSize -= 8;
offset += 8;
-
+
uint32_t chunkSize = U32_LE_AT(&chunkHeader[4]);
if (chunkSize > remainingSize) {
@@ -178,7 +172,13 @@
mSampleRate = U32_LE_AT(&formatSpec[4]);
- if (U16_LE_AT(&formatSpec[14]) != 16) {
+ if (mSampleRate == 0) {
+ return ERROR_MALFORMED;
+ }
+
+ mBitsPerSample = U16_LE_AT(&formatSpec[14]);
+
+ if (mBitsPerSample != 8 && mBitsPerSample != 16) {
return ERROR_UNSUPPORTED;
}
@@ -188,6 +188,19 @@
mDataOffset = offset;
mDataSize = chunkSize;
+ mTrackMeta = new MetaData;
+ mTrackMeta->setCString(kKeyMIMEType, MEDIA_MIMETYPE_AUDIO_RAW);
+ mTrackMeta->setInt32(kKeyChannelCount, mNumChannels);
+ mTrackMeta->setInt32(kKeySampleRate, mSampleRate);
+
+ size_t bytesPerSample = mBitsPerSample >> 3;
+
+ int64_t durationUs =
+ 1000000LL * (mDataSize / (mNumChannels * bytesPerSample))
+ / mSampleRate;
+
+ mTrackMeta->setInt64(kKeyDuration, durationUs);
+
return OK;
}
}
@@ -202,15 +215,20 @@
WAVSource::WAVSource(
const sp<DataSource> &dataSource,
- int32_t sampleRate, int32_t numChannels,
+ const sp<MetaData> &meta,
+ int32_t bitsPerSample,
off_t offset, size_t size)
: mDataSource(dataSource),
- mSampleRate(sampleRate),
- mNumChannels(numChannels),
+ mMeta(meta),
+ mSampleRate(0),
+ mNumChannels(0),
+ mBitsPerSample(bitsPerSample),
mOffset(offset),
mSize(size),
mStarted(false),
mGroup(NULL) {
+ CHECK(mMeta->findInt32(kKeySampleRate, &mSampleRate));
+ CHECK(mMeta->findInt32(kKeyChannelCount, &mNumChannels));
}
WAVSource::~WAVSource() {
@@ -227,6 +245,11 @@
mGroup = new MediaBufferGroup;
mGroup->add_buffer(new MediaBuffer(kMaxFrameSize));
+ if (mBitsPerSample == 8) {
+ // As a temporary buffer for 8->16 bit conversion.
+ mGroup->add_buffer(new MediaBuffer(kMaxFrameSize));
+ }
+
mCurrentPos = mOffset;
mStarted = true;
@@ -250,17 +273,7 @@
sp<MetaData> WAVSource::getFormat() {
LOGV("WAVSource::getFormat");
- sp<MetaData> meta = new MetaData;
- meta->setCString(kKeyMIMEType, MEDIA_MIMETYPE_AUDIO_RAW);
- meta->setInt32(kKeyChannelCount, mNumChannels);
- meta->setInt32(kKeySampleRate, mSampleRate);
-
- int64_t durationUs =
- 1000000LL * (mSize / (mNumChannels * 2)) / mSampleRate;
-
- meta->setInt64(kKeyDuration, durationUs);
-
- return meta;
+ return mMeta;
}
status_t WAVSource::read(
@@ -283,7 +296,8 @@
}
ssize_t n = mDataSource->readAt(
- mCurrentPos, buffer->data(), kMaxFrameSize);
+ mCurrentPos, buffer->data(),
+ mBitsPerSample == 8 ? kMaxFrameSize / 2 : kMaxFrameSize);
if (n <= 0) {
buffer->release();
@@ -295,10 +309,34 @@
mCurrentPos += n;
buffer->set_range(0, n);
+
+ if (mBitsPerSample == 8) {
+ // Convert 8-bit unsigned samples to 16-bit signed.
+
+ MediaBuffer *tmp;
+ CHECK_EQ(mGroup->acquire_buffer(&tmp), OK);
+
+ // The new buffer holds the sample number of samples, but each
+ // one is 2 bytes wide.
+ tmp->set_range(0, 2 * n);
+
+ int16_t *dst = (int16_t *)tmp->data();
+ const uint8_t *src = (const uint8_t *)buffer->data();
+ while (n-- > 0) {
+ *dst++ = ((int16_t)(*src) - 128) * 256;
+ ++src;
+ }
+
+ buffer->release();
+ buffer = tmp;
+ }
+
+ size_t bytesPerSample = mBitsPerSample >> 3;
+
buffer->meta_data()->setInt64(
kKeyTime,
1000000LL * (mCurrentPos - mOffset)
- / (mNumChannels * 2) / mSampleRate);
+ / (mNumChannels * bytesPerSample) / mSampleRate);
*out = buffer;
diff --git a/media/libstagefright/include/WAVExtractor.h b/media/libstagefright/include/WAVExtractor.h
index 8545efc..9384942 100644
--- a/media/libstagefright/include/WAVExtractor.h
+++ b/media/libstagefright/include/WAVExtractor.h
@@ -45,8 +45,10 @@
bool mValidFormat;
uint16_t mNumChannels;
uint32_t mSampleRate;
+ uint16_t mBitsPerSample;
off_t mDataOffset;
size_t mDataSize;
+ sp<MetaData> mTrackMeta;
status_t init();
