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Diffstat (limited to 'src/lib/formats/flacfile.cpp')
-rw-r--r--src/lib/formats/flacfile.cpp78
1 files changed, 74 insertions, 4 deletions
diff --git a/src/lib/formats/flacfile.cpp b/src/lib/formats/flacfile.cpp
index f3ccb676e52..c594a809a8e 100644
--- a/src/lib/formats/flacfile.cpp
+++ b/src/lib/formats/flacfile.cpp
@@ -16,10 +16,27 @@
#include <new>
-static constexpr int MAX_CHANNELS = 8;
+namespace {
+constexpr int MAX_CHANNELS = 8;
-static cassette_image::error flacfile_identify(cassette_image *cassette, cassette_image::Options *opts)
+
+// Copied from cassimg.cpp; put somewhere central?
+/*********************************************************************
+ helper code
+*********************************************************************/
+constexpr double map_double(double d, uint64_t low, uint64_t high, uint64_t value)
+{
+ return d * (value - low) / (high - low);
+}
+
+constexpr size_t waveform_bytes_per_sample(int waveform_flags)
+{
+ return size_t(1 << ((waveform_flags & 0x06) / 2));
+}
+
+
+cassette_image::error flacfile_identify(cassette_image *cassette, cassette_image::Options *opts)
{
cassette->get_raw_cassette_image()->seek(0, SEEK_SET);
flac_decoder decoder(*cassette->get_raw_cassette_image());
@@ -42,7 +59,7 @@ static cassette_image::error flacfile_identify(cassette_image *cassette, cassett
}
-static cassette_image::error flacfile_load(cassette_image *cassette)
+cassette_image::error flacfile_load(cassette_image *cassette)
{
cassette->get_raw_cassette_image()->seek(0, SEEK_SET);
flac_decoder decoder(*cassette->get_raw_cassette_image());
@@ -73,10 +90,63 @@ static cassette_image::error flacfile_load(cassette_image *cassette)
}
+cassette_image::error flacfile_save(cassette_image *cassette, const cassette_image::Info *info)
+{
+ if (info->channels > MAX_CHANNELS)
+ return cassette_image::error::INVALID_IMAGE;
+
+ cassette->get_raw_cassette_image()->seek(0, SEEK_SET);
+ flac_encoder encoder;
+ encoder.set_num_channels(info->channels);
+ encoder.set_sample_rate(info->sample_frequency);
+ if (!encoder.reset(*cassette->get_raw_cassette_image()))
+ return cassette_image::error::INTERNAL;
+
+ size_t samples_saved = 0;
+ int16_t buffer[MAX_CHANNELS][4096];
+ int16_t *buffer_ptr[MAX_CHANNELS];
+ const size_t bytes_per_sample = waveform_bytes_per_sample(cassette_image::WAVEFORM_16BIT);
+ const size_t sample_spacing = bytes_per_sample * info->channels;
+ const double sample_period = info->sample_count / (double) info->sample_frequency;
+
+ for (int channel = 0; channel < MAX_CHANNELS; channel++)
+ {
+ buffer_ptr[channel] = &buffer[channel][0];
+ }
+
+ while (samples_saved < info->sample_count)
+ {
+ size_t chunk_sample_count = std::min(sizeof(buffer) / sample_spacing, (info->sample_count - samples_saved));
+ double chunk_sample_period = map_double(sample_period, 0, info->sample_count, chunk_sample_count);
+ double chunk_time_index = map_double(sample_period, 0, info->sample_count, samples_saved);
+
+ for (int channel = 0; channel < info->channels; channel++)
+ {
+ cassette_image::error err = cassette->get_samples(channel, chunk_time_index, chunk_sample_period,
+ chunk_sample_count, sample_spacing, &buffer[channel * bytes_per_sample], cassette_image::WAVEFORM_16BIT);
+
+ if (err != cassette_image::error::SUCCESS)
+ return err;
+ }
+
+ if (!encoder.encode(buffer_ptr, chunk_sample_count))
+ return cassette_image::error::INTERNAL;
+
+ samples_saved += chunk_sample_count;
+ }
+
+ encoder.finish();
+
+ return cassette_image::error::SUCCESS;
+}
+
+} // anonymous namespace
+
+
const cassette_image::Format cassette_image::flacfile_format =
{
"flac",
flacfile_identify,
flacfile_load,
- nullptr
+ flacfile_save
};