X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=nageru%2Faudio_mixer.cpp;h=360689b83406b04e6737cb6b7815d4092aca0a90;hb=8206e97bbc404b36e67b981d63e761ab9ce07c4f;hp=9b588d704d63303dccd354a40bafcbc7431f6d69;hpb=9ffd4f03f314cc6e0254449593def95c9bc203d6;p=nageru

diff --git a/nageru/audio_mixer.cpp b/nageru/audio_mixer.cpp
index 9b588d7..360689b 100644
--- a/nageru/audio_mixer.cpp
+++ b/nageru/audio_mixer.cpp
@@ -52,6 +52,26 @@ void convert_fixed16_to_fp32(float *dst, size_t out_channel, size_t out_num_chan
 	}
 }
 
+void convert_fixed16_to_fixed32(int32_t *dst, size_t out_channel, size_t out_num_channels,
+                                const uint8_t *src, size_t in_channel, size_t in_num_channels,
+                                size_t num_samples)
+{
+	assert(in_channel < in_num_channels);
+	assert(out_channel < out_num_channels);
+	src += in_channel * 2;
+	dst += out_channel;
+
+	for (size_t i = 0; i < num_samples; ++i) {
+		uint32_t s = uint32_t(uint16_t(le16toh(*(int16_t *)src))) << 16;
+
+		// Keep the sign bit in place, repeat the other 15 bits as far as they go.
+		*dst = s | ((s & 0x7fffffff) >> 15) | ((s & 0x7fffffff) >> 30);
+
+		src += 2 * in_num_channels;
+		dst += out_num_channels;
+	}
+}
+
 void convert_fixed24_to_fp32(float *dst, size_t out_channel, size_t out_num_channels,
                              const uint8_t *src, size_t in_channel, size_t in_num_channels,
                              size_t num_samples)
@@ -73,6 +93,29 @@ void convert_fixed24_to_fp32(float *dst, size_t out_channel, size_t out_num_chan
 	}
 }
 
+void convert_fixed24_to_fixed32(int32_t *dst, size_t out_channel, size_t out_num_channels,
+                                const uint8_t *src, size_t in_channel, size_t in_num_channels,
+                                size_t num_samples)
+{
+	assert(in_channel < in_num_channels);
+	assert(out_channel < out_num_channels);
+	src += in_channel * 3;
+	dst += out_channel;
+
+	for (size_t i = 0; i < num_samples; ++i) {
+		uint32_t s1 = src[0];
+		uint32_t s2 = src[1];
+		uint32_t s3 = src[2];
+		uint32_t s = (s1 << 8) | (s2 << 16) | (s3 << 24);
+
+		// Keep the sign bit in place, repeat the other 23 bits as far as they go.
+		*dst = s | ((s & 0x7fffffff) >> 23);
+
+		src += 3 * in_num_channels;
+		dst += out_num_channels;
+	}
+}
+
 void convert_fixed32_to_fp32(float *dst, size_t out_channel, size_t out_num_channels,
                              const uint8_t *src, size_t in_channel, size_t in_num_channels,
                              size_t num_samples)
@@ -91,6 +134,25 @@ void convert_fixed32_to_fp32(float *dst, size_t out_channel, size_t out_num_chan
 	}
 }
 
+// Basically just a reinterleave.
+void convert_fixed32_to_fixed32(int32_t *dst, size_t out_channel, size_t out_num_channels,
+                                const uint8_t *src, size_t in_channel, size_t in_num_channels,
+                                size_t num_samples)
+{
+	assert(in_channel < in_num_channels);
+	assert(out_channel < out_num_channels);
+	src += in_channel * 4;
+	dst += out_channel;
+
+	for (size_t i = 0; i < num_samples; ++i) {
+		int32_t s = le32toh(*(int32_t *)src);
+		*dst = s;
+
+		src += 4 * in_num_channels;
+		dst += out_num_channels;
+	}
+}
+
 float find_peak_plain(const float *samples, size_t num_samples) __attribute__((unused));
 
 float find_peak_plain(const float *samples, size_t num_samples)
@@ -294,6 +356,38 @@ bool AudioMixer::add_audio(DeviceSpec device_spec, const uint8_t *data, unsigned
 	return true;
 }
 
+vector<int32_t> convert_audio_to_fixed32(const uint8_t *data, unsigned num_samples, bmusb::AudioFormat audio_format, unsigned num_channels)
+{
+	vector<int32_t> audio;
+
+	if (num_channels > audio_format.num_channels) {
+		audio.resize(num_samples * num_channels, 0);
+	} else {
+		audio.resize(num_samples * num_channels);
+	}
+	for (unsigned channel_index = 0; channel_index < num_channels && channel_index < audio_format.num_channels; ++channel_index) {
+		switch (audio_format.bits_per_sample) {
+		case 0:
+			assert(num_samples == 0);
+			break;
+		case 16:
+			convert_fixed16_to_fixed32(&audio[0], channel_index, num_channels, data, channel_index, audio_format.num_channels, num_samples);
+			break;
+		case 24:
+			convert_fixed24_to_fixed32(&audio[0], channel_index, num_channels, data, channel_index, audio_format.num_channels, num_samples);
+			break;
+		case 32:
+			convert_fixed32_to_fixed32(&audio[0], channel_index, num_channels, data, channel_index, audio_format.num_channels, num_samples);
+			break;
+		default:
+			fprintf(stderr, "Cannot handle audio with %u bits per sample\n", audio_format.bits_per_sample);
+			assert(false);
+		}
+	}
+
+	return audio;
+}
+
 bool AudioMixer::add_silence(DeviceSpec device_spec, unsigned samples_per_frame, unsigned num_frames)
 {
 	AudioDevice *device = find_audio_device(device_spec);