core/hrseek: support precise seeks in audio-only case

Before, precise seeking only worked if there was a video stream; in
the audio-only case playback always started from the demuxer seek
position. Add code to cut away samples from the demuxer seek position
to the seek target position.

1 files changed, 18 insertions, 4 deletions

diff --git a/mplayer.c b/mplayer.c
index 7030a50da0..c13f56a143 100644
--- a/mplayer.c
+++ b/mplayer.c
@@ -2464,10 +2464,16 @@ static int audio_start_sync(struct MPContext *mpctx, int playsize)
     bool did_retry = false;
     double written_pts;
     double bps = ao->bps / opts->playback_speed;
+    bool hrseek = mpctx->hrseek_active;   // audio only hrseek
+    mpctx->hrseek_active = false;
     while (1) {
         written_pts = written_audio_pts(mpctx);
-        double ptsdiff = written_pts - mpctx->sh_video->pts - mpctx->delay
-                         - audio_delay;
+        double ptsdiff;
+        if (hrseek)
+            ptsdiff = written_pts - mpctx->hrseek_pts;
+        else
+            ptsdiff = written_pts - mpctx->sh_video->pts - mpctx->delay
+                      - audio_delay;
         bytes = ptsdiff * bps;
         bytes -= bytes % (ao->channels * af_fmt2bits(ao->format) / 8);
 
@@ -2506,6 +2512,9 @@ static int audio_start_sync(struct MPContext *mpctx, int playsize)
         if (res < 0)
             return res;
     }
+    if (hrseek)
+        // Don't add silence in audio-only case even if position is too late
+        return 0;
     int fillbyte = 0;
     if ((ao->format & AF_FORMAT_SIGN_MASK) == AF_FORMAT_US)
         fillbyte = 0x80;
@@ -2557,11 +2566,16 @@ static int fill_audio_out_buffers(struct MPContext *mpctx)
     current_module = "decode_audio";
     t = GetTimer();
 
-    if (!opts->initial_audio_sync || !modifiable_audio_format)
+    // Coming here with hrseek_active still set means audio-only
+    if (!mpctx->sh_video)
+        mpctx->syncing_audio = false;
+    if (!opts->initial_audio_sync || !modifiable_audio_format) {
         mpctx->syncing_audio = false;
+        mpctx->hrseek_active = false;
+    }
 
     int res;
-    if (mpctx->syncing_audio && mpctx->sh_video)
+    if (mpctx->syncing_audio || mpctx->hrseek_active)
         res = audio_start_sync(mpctx, playsize);
     else
         res = decode_audio(sh_audio, &ao->buffer, playsize);