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chore: remove code that pretends to remove DC offset

This commit is contained in:
Rekai Nyangadzayi Musuka 2022-10-21 05:12:48 -03:00
parent 02fee16561
commit 89619596ad
2 changed files with 4 additions and 7 deletions
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9
src/apu.zig
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@ -180,8 +180,8 @@ pub const Apu = struct {
left += bias;
right += bias;
const tmp_left = std.math.clamp(@intCast(u16, left), std.math.minInt(u11), std.math.maxInt(u11));
const tmp_right = std.math.clamp(@intCast(u16, right), std.math.minInt(u11), std.math.maxInt(u11));
const tmp_left = std.math.clamp(@bitCast(u16, left), std.math.minInt(u11), std.math.maxInt(u11));
const tmp_right = std.math.clamp(@bitCast(u16, right), std.math.minInt(u11), std.math.maxInt(u11));
// Extend to 16-bit signed audio samples
const final_left = (tmp_left << 5) | (tmp_left >> 6);
@ -199,10 +199,7 @@ pub const Apu = struct {
self.stream = SDL.SDL_NewAudioStream(SDL.AUDIO_U16, 2, @intCast(c_int, self.sampleRate()), SDL.AUDIO_U16, 2, host_sample_rate) orelse unreachable;
}
// If we add 0x4040 to each sample the DC Offset is removed
// note: found this through guess and check
// FIXME: Pretty sure this is a dirty hack and should be fixed
_ = SDL.SDL_AudioStreamPut(self.stream, &[2]u16{ final_left + 0x4040, final_right + 0x4040 }, 2 * @sizeOf(u16));
_ = SDL.SDL_AudioStreamPut(self.stream, &[2]u16{ final_left, final_right }, 2 * @sizeOf(u16));
self.sched.push(.SampleAudio, self.sampleTicks() -| late);
}

2
src/main.zig
View File

@ -245,7 +245,7 @@ export fn audioCallback(userdata: ?*anyopaque, stream: [*c]u8, len: c_int) void
// If we don't write anything, play silence otherwise garbage will be played
// FIXME: I don't think this hack to remove DC Offset is acceptable :thinking:
if (written == 0) std.mem.set(u8, stream[0..@intCast(usize, len)], 0x80);
if (written == 0) std.mem.set(u8, stream[0..@intCast(usize, len)], 0x40);
}
fn getSavePath(alloc: std.mem.Allocator) !?[]const u8 {