From 2788e848f84b215541420e79944e8fe39d29fc6b Mon Sep 17 00:00:00 2001
From: Brick <[EMAIL REDACTED]>
Date: Sun, 20 Aug 2023 19:50:54 +0100
Subject: [PATCH] Allow resampling less than 1 frame of input
---
src/audio/SDL_audiocvt.c | 12 +-----------
1 file changed, 1 insertion(+), 11 deletions(-)
diff --git a/src/audio/SDL_audiocvt.c b/src/audio/SDL_audiocvt.c
index 1eab59a61c9e..5caec70792a8 100644
--- a/src/audio/SDL_audiocvt.c
+++ b/src/audio/SDL_audiocvt.c
@@ -867,17 +867,6 @@ static int GetAudioStreamDataInternal(SDL_AudioStream *stream, void *buf, int le
if (resample_rate) {
input_frames = GetResamplerNeededInputFrames(output_frames, resample_rate, stream->resample_offset);
-
- if (input_frames == 0) { // uhoh, not enough input frames!
- // if they are upsampling and we end up needing less than a frame of input, we reject it because it would cause artifacts on future reads to eat a full input frame.
- // however, if the stream is flushed, we would just be padding any remaining input with silence anyhow, so use it up.
- if (stream->flushed) {
- SDL_assert(((size_t) ((input_frames * src_sample_frame_size) + future_buffer_filled_frames)) <= stream->future_buffer_allocation);
- // leave input_frames alone; this will just shuffle what's available from the future buffer and pad with silence as appropriate, below.
- } else {
- return 0;
- }
- }
}
// !!! FIXME: this could be less aggressive about allocation, if we decide the necessary size at each stage and select the maximum required.
@@ -958,6 +947,7 @@ static int GetAudioStreamDataInternal(SDL_AudioStream *stream, void *buf, int le
const int history_buffer_bytes = history_buffer_frames * src_sample_frame_size;
const int request_bytes = workbuf_frames * src_sample_frame_size;
if (history_buffer_frames > workbuf_frames) {
+ // FIXME: This gets exponentially slower as the request gets smaller
const int preserve_bytes = history_buffer_bytes - request_bytes;
SDL_memmove(history_buffer, history_buffer + request_bytes, preserve_bytes);
SDL_memcpy(history_buffer + preserve_bytes, workbuf, request_bytes);