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authorVolker Rümelin <vr_qemu@t-online.de>2023-02-24 20:05:52 +0100
committerMarc-André Lureau <marcandre.lureau@redhat.com>2023-03-06 10:30:23 +0400
commita9ea567873ba8d532520f194413ff28f37065c00 (patch)
treec25cdae272de3f9ffbd94439cc7255496cd9c50f /audio/audio.c
parentfbde1edf06dad792ef3e9f51e3f52a49669bdd40 (diff)
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audio: make recording packet length calculation exact
Introduce the new function st_rate_frames_out() to calculate the exact number of audio output frames the resampling code can generate from a given number of audio input frames. When upsampling, this function returns the maximum number of output frames. This new function replaces the audio_frontend_frames_in() function, which calculated the average number of output frames rounded down to the nearest integer. The audio_frontend_frames_in() function was additionally used to limit the number of output frames to the resample buffer size. In audio_pcm_sw_read() the variable resample_buf.size replaces the open coded audio_frontend_frames_in() function. In audio_run_in() an additional MIN() function is necessary. After this patch the audio packet length calculation for audio recording is exact. Acked-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk> Signed-off-by: Volker Rümelin <vr_qemu@t-online.de> Message-Id: <20230224190555.7409-12-vr_qemu@t-online.de>
Diffstat (limited to 'audio/audio.c')
-rw-r--r--audio/audio.c29
1 files changed, 8 insertions, 21 deletions
diff --git a/audio/audio.c b/audio/audio.c
index 22c36d6..dad17e5 100644
--- a/audio/audio.c
+++ b/audio/audio.c
@@ -579,7 +579,7 @@ static void audio_pcm_sw_resample_in(SWVoiceIn *sw,
static size_t audio_pcm_sw_read(SWVoiceIn *sw, void *buf, size_t buf_len)
{
HWVoiceIn *hw = sw->hw;
- size_t live, frames_out_max, swlim, total_in, total_out;
+ size_t live, frames_out_max, total_in, total_out;
live = hw->total_samples_captured - sw->total_hw_samples_acquired;
if (!live) {
@@ -590,12 +590,10 @@ static size_t audio_pcm_sw_read(SWVoiceIn *sw, void *buf, size_t buf_len)
return 0;
}
- frames_out_max = buf_len / sw->info.bytes_per_frame;
+ frames_out_max = MIN(buf_len / sw->info.bytes_per_frame,
+ sw->resample_buf.size);
- swlim = (live * sw->ratio) >> 32;
- swlim = MIN(swlim, frames_out_max);
-
- audio_pcm_sw_resample_in(sw, live, swlim, &total_in, &total_out);
+ audio_pcm_sw_resample_in(sw, live, frames_out_max, &total_in, &total_out);
if (!hw->pcm_ops->volume_in) {
mixeng_volume(sw->resample_buf.buffer, total_out, &sw->vol);
@@ -979,18 +977,6 @@ void AUD_set_active_in (SWVoiceIn *sw, int on)
}
}
-/**
- * audio_frontend_frames_in() - returns the number of frames the resampling
- * code generates from frames_in frames
- *
- * @sw: audio recording frontend
- * @frames_in: number of frames
- */
-static size_t audio_frontend_frames_in(SWVoiceIn *sw, size_t frames_in)
-{
- return (int64_t)frames_in * sw->ratio >> 32;
-}
-
static size_t audio_get_avail (SWVoiceIn *sw)
{
size_t live;
@@ -1007,9 +993,9 @@ static size_t audio_get_avail (SWVoiceIn *sw)
}
ldebug (
- "%s: get_avail live %zu frontend frames %zu\n",
+ "%s: get_avail live %zu frontend frames %u\n",
SW_NAME (sw),
- live, audio_frontend_frames_in(sw, live)
+ live, st_rate_frames_out(sw->rate, live)
);
return live;
@@ -1314,8 +1300,9 @@ static void audio_run_in (AudioState *s)
size_t sw_avail = audio_get_avail(sw);
size_t avail;
- avail = audio_frontend_frames_in(sw, sw_avail);
+ avail = st_rate_frames_out(sw->rate, sw_avail);
if (avail > 0) {
+ avail = MIN(avail, sw->resample_buf.size);
sw->callback.fn(sw->callback.opaque,
avail * sw->info.bytes_per_frame);
}