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C++ BBuffer::SetSizeUsed方法代码示例

本文整理汇总了C++中BBuffer::SetSizeUsed方法的典型用法代码示例。如果您正苦于以下问题:C++ BBuffer::SetSizeUsed方法的具体用法?C++ BBuffer::SetSizeUsed怎么用?C++ BBuffer::SetSizeUsed使用的例子?那么, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在BBuffer的用法示例。


在下文中一共展示了BBuffer::SetSizeUsed方法的1个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的C++代码示例。

示例1: message

BBuffer*
AudioProducer::_FillNextBuffer(bigtime_t eventTime)
{
	BBuffer* buffer = fBufferGroup->RequestBuffer(
		fOutput.format.u.raw_audio.buffer_size, BufferDuration());

	if (!buffer) {
		ERROR("AudioProducer::_FillNextBuffer() - no buffer\n");
		return NULL;
	}

	size_t sampleSize = fOutput.format.u.raw_audio.format
		& media_raw_audio_format::B_AUDIO_SIZE_MASK;
	size_t numSamples = fOutput.format.u.raw_audio.buffer_size / sampleSize;
		// number of sample in the buffer

	// fill in the buffer header
	media_header* header = buffer->Header();
	header->type = B_MEDIA_RAW_AUDIO;
	header->time_source = TimeSource()->ID();
	buffer->SetSizeUsed(fOutput.format.u.raw_audio.buffer_size);

	bigtime_t performanceTime = bigtime_t(double(fFramesSent)
		* 1000000.0 / double(fOutput.format.u.raw_audio.frame_rate));

	// fill in data from audio supplier
	int64 frameCount = numSamples / fOutput.format.u.raw_audio.channel_count;
	bigtime_t startTime = performanceTime;
	bigtime_t endTime = bigtime_t(double(fFramesSent + frameCount)
		* 1000000.0 / fOutput.format.u.raw_audio.frame_rate);

	if (!fSupplier || fSupplier->InitCheck() != B_OK
		|| fSupplier->GetFrames(buffer->Data(), frameCount, startTime,
			endTime) != B_OK) {
		ERROR("AudioProducer::_FillNextBuffer() - supplier error -> silence\n");
		memset(buffer->Data(), 0, buffer->SizeUsed());
	}

	// stamp buffer
	if (RunMode() == B_RECORDING) {
		header->start_time = eventTime;
	} else {
		header->start_time = fStartTime + performanceTime;
	}

#if DEBUG_TO_FILE
	BMediaTrack* track;
	if (BMediaFile* file = init_media_file(fOutput.format, &track)) {
		track->WriteFrames(buffer->Data(), frameCount);
	}
#endif // DEBUG_TO_FILE

	if (fPeakListener
		&& fOutput.format.u.raw_audio.format
			== media_raw_audio_format::B_AUDIO_FLOAT) {
		// TODO: extend the peak notifier for other sample formats
		int32 channels = fOutput.format.u.raw_audio.channel_count;
		float max[channels];
		float min[channels];
		for (int32 i = 0; i < channels; i++) {
			max[i] = -1.0;
			min[i] = 1.0;
		}
		float* sample = (float*)buffer->Data();
		for (uint32 i = 0; i < frameCount; i++) {
			for (int32 k = 0; k < channels; k++) {
				if (*sample < min[k])
					min[k] = *sample;
				if (*sample > max[k])
					max[k] = *sample;
				sample++;
			}
		}
		BMessage message(MSG_PEAK_NOTIFICATION);
		for (int32 i = 0; i < channels; i++) {
			float maxAbs = max_c(fabs(min[i]), fabs(max[i]));
			message.AddFloat("max", maxAbs);
		}
		bigtime_t realTime = TimeSource()->RealTimeFor(
			fStartTime + performanceTime, 0);
		MessageEvent* event = new (std::nothrow) MessageEvent(realTime,
			fPeakListener, message);
		if (event != NULL)
			EventQueue::Default().AddEvent(event);
	}

	return buffer;
}
开发者ID:mariuz,项目名称:haiku,代码行数:88,代码来源:AudioProducer.cpp


注:本文中的BBuffer::SetSizeUsed方法示例由纯净天空整理自Github/MSDocs等开源代码及文档管理平台,相关代码片段筛选自各路编程大神贡献的开源项目,源码版权归原作者所有,传播和使用请参考对应项目的License;未经允许,请勿转载。