namespace media {
+static base::TimeDelta CalculateDuration(int frames, double sample_rate) {
+ DCHECK_GT(sample_rate, 0);
+ return base::TimeDelta::FromMicroseconds(
+ frames * base::Time::kMicrosecondsPerSecond / sample_rate);
+}
+
AudioBuffer::AudioBuffer(SampleFormat sample_format,
ChannelLayout channel_layout,
int channel_count,
int frame_count,
bool create_buffer,
const uint8* const* data,
- const base::TimeDelta timestamp,
- const base::TimeDelta duration)
+ const base::TimeDelta timestamp)
: sample_format_(sample_format),
channel_layout_(channel_layout),
channel_count_(channel_count),
trim_start_(0),
end_of_stream_(!create_buffer && data == NULL && frame_count == 0),
timestamp_(timestamp),
- duration_(duration) {
+ duration_(end_of_stream_
+ ? base::TimeDelta()
+ : CalculateDuration(adjusted_frame_count_, sample_rate_)) {
CHECK_GE(channel_count_, 0);
CHECK_LE(channel_count_, limits::kMaxChannels);
CHECK_GE(frame_count, 0);
int sample_rate,
int frame_count,
const uint8* const* data,
- const base::TimeDelta timestamp,
- const base::TimeDelta duration) {
+ const base::TimeDelta timestamp) {
// If you hit this CHECK you likely have a bug in a demuxer. Go fix it.
CHECK_GT(frame_count, 0); // Otherwise looks like an EOF buffer.
CHECK(data[0]);
frame_count,
true,
data,
- timestamp,
- duration));
+ timestamp));
}
// static
frame_count,
true,
NULL,
- kNoTimestamp(),
kNoTimestamp()));
}
int channel_count,
int sample_rate,
int frame_count,
- const base::TimeDelta timestamp,
- const base::TimeDelta duration) {
+ const base::TimeDelta timestamp) {
CHECK_GT(frame_count, 0); // Otherwise looks like an EOF buffer.
// Since data == NULL, format doesn't matter.
return make_scoped_refptr(new AudioBuffer(kSampleFormatF32,
frame_count,
false,
NULL,
- timestamp,
- duration));
+ timestamp));
}
// static
0,
false,
NULL,
- kNoTimestamp(),
kNoTimestamp()));
}
CHECK_GE(frames_to_trim, 0);
CHECK_LE(frames_to_trim, adjusted_frame_count_);
- // Adjust timestamp_ and duration_ to reflect the smaller number of frames.
- double offset = static_cast<double>(duration_.InMicroseconds()) *
- frames_to_trim / adjusted_frame_count_;
- base::TimeDelta offset_as_time =
- base::TimeDelta::FromMicroseconds(static_cast<int64>(offset));
- timestamp_ += offset_as_time;
- duration_ -= offset_as_time;
-
- // Finally adjust the number of frames in this buffer and where the start
- // really is.
+ // Adjust the number of frames in this buffer and where the start really is.
adjusted_frame_count_ -= frames_to_trim;
trim_start_ += frames_to_trim;
+
+ // Adjust timestamp_ and duration_ to reflect the smaller number of frames.
+ const base::TimeDelta old_duration = duration_;
+ duration_ = CalculateDuration(adjusted_frame_count_, sample_rate_);
+ timestamp_ += old_duration - duration_;
}
void AudioBuffer::TrimEnd(int frames_to_trim) {
CHECK_GE(frames_to_trim, 0);
CHECK_LE(frames_to_trim, adjusted_frame_count_);
- // Adjust duration_ only to reflect the smaller number of frames.
- double offset = static_cast<double>(duration_.InMicroseconds()) *
- frames_to_trim / adjusted_frame_count_;
- base::TimeDelta offset_as_time =
- base::TimeDelta::FromMicroseconds(static_cast<int64>(offset));
- duration_ -= offset_as_time;
-
- // Finally adjust the number of frames in this buffer.
+ // Adjust the number of frames and duration for this buffer.
adjusted_frame_count_ -= frames_to_trim;
+ duration_ = CalculateDuration(adjusted_frame_count_, sample_rate_);
+}
+
+void AudioBuffer::TrimRange(int start, int end) {
+ CHECK_GE(start, 0);
+ CHECK_LE(end, adjusted_frame_count_);
+
+ const int frames_to_trim = end - start;
+ CHECK_GE(frames_to_trim, 0);
+ CHECK_LE(frames_to_trim, adjusted_frame_count_);
+
+ const int bytes_per_channel = SampleFormatToBytesPerChannel(sample_format_);
+ const int frames_to_copy = adjusted_frame_count_ - end;
+ if (frames_to_copy > 0) {
+ switch (sample_format_) {
+ case kSampleFormatPlanarS16:
+ case kSampleFormatPlanarF32:
+ // Planar data must be shifted per channel.
+ for (int ch = 0; ch < channel_count_; ++ch) {
+ memmove(channel_data_[ch] + (trim_start_ + start) * bytes_per_channel,
+ channel_data_[ch] + (trim_start_ + end) * bytes_per_channel,
+ bytes_per_channel * frames_to_copy);
+ }
+ break;
+ case kSampleFormatU8:
+ case kSampleFormatS16:
+ case kSampleFormatS32:
+ case kSampleFormatF32: {
+ // Interleaved data can be shifted all at once.
+ const int frame_size = channel_count_ * bytes_per_channel;
+ memmove(channel_data_[0] + (trim_start_ + start) * frame_size,
+ channel_data_[0] + (trim_start_ + end) * frame_size,
+ frame_size * frames_to_copy);
+ break;
+ }
+ case kUnknownSampleFormat:
+ NOTREACHED() << "Invalid sample format!";
+ }
+ } else {
+ CHECK_EQ(frames_to_copy, 0);
+ }
+
+ // Trim the leftover data off the end of the buffer and update duration.
+ TrimEnd(frames_to_trim);
}
} // namespace media