Rework Level Detection / Chroma Transient Improvement

lddecode/core.py

@@ -2651,6 +2651,7 @@ def downscale(
         audio=0,
         final=False,
         lastfieldwritten=None,
+        shift=0
     ):
         if lineinfo is None:
             lineinfo = self.linelocs
@@ -2717,7 +2718,8 @@ def downscale(
             self.rf.downscale_sinc_lut,
             self.lineoffset,
             outwidth,
-            wow_level_adjust_smoothing=self.wow_level_adjust_smoothing
+            wow_level_adjust_smoothing=self.wow_level_adjust_smoothing,
+            shift=shift
         )
 
         if self.rf.decode_digital_audio:

lddecode/utils.py

@@ -143,7 +143,7 @@ def scale(buf, begin, end, tgtlen, mult=1):
 
 
 @njit(nogil=True, fastmath=True)
-def scale_field(buf, dsout, interpolated_pixel_locs, wowfactors, sinc_lut, lineoffset, outwidth, wow_level_adjust_smoothing = 0, level_adjust_threshold = 15):
+def scale_field(buf, dsout, interpolated_pixel_locs, wowfactors, sinc_lut, lineoffset, outwidth, wow_level_adjust_smoothing = 0, level_adjust_threshold = 15, shift=0.0):
     # average out any unusual spikes in wow that happen on a per line basis
     # this indicates an hsync tbc error vs. being normal wow from playback speed variations
     # in this case for level adjusting we just want to fallback to the average wow to avoid a bright or dark line
@@ -175,7 +175,8 @@ def scale_field(buf, dsout, interpolated_pixel_locs, wowfactors, sinc_lut, lineo
         level_adjust = level_adjusts[i]
 
         # reconstructs the waveform at the proper fractional sample position, undoing wow-induced timing variations
-        coord = np.float32(interpolated_pixel_locs[i])
+        # Adding the positive shift pulls future (late) samples backward into alignment.
+        coord = np.float32(interpolated_pixel_locs[i] + shift)
         coord_int = int(coord)
 
         # fractional phase

tests.py

@@ -91,10 +91,8 @@ def test_sync(filename, num_pulses=None, blank_approx=None, sync_approx=None):
     ldd.logger.info("test")
 
     # process.VHSDecode("infile", "outfile", ,inputfreq=samplerate_mhz, system="PAL", tape_format="VHS")
-    rf_options = {}
-    rf_options["level_detect_divisor"] = 2
     rfdecoder = process.VHSRFDecode(
-        inputfreq=samplerate_mhz, system="PAL", tape_format="VHS", rf_options=rf_options
+        inputfreq=samplerate_mhz, system="PAL", tape_format="VHS"
     )
 
     demod_05_data = np.loadtxt(filename)
@@ -107,12 +105,13 @@ def test_sync(filename, num_pulses=None, blank_approx=None, sync_approx=None):
 
     field = FieldPALVHS(rfdecoder, data_stub)
 
-    pulses = rfdecoder.resync.get_pulses(field)
+    pulses = field.get_pulses()
 
     if num_pulses:
         assert len(pulses) == num_pulses
 
-    measured_sync, measured_blank = rfdecoder.resync._field_state.pull_levels()
+    measured_sync = field.sync_tip_level
+    measured_blank = field.blanking_level
 
     if blank_approx:
         assert math.isclose(measured_blank, blank_approx)
@@ -122,20 +121,6 @@ def test_sync(filename, num_pulses=None, blank_approx=None, sync_approx=None):
     return True
 
 
-def test_find_pulses(filename, num_pulses):
-    from vhsdecode.addons.resync import _findpulses_numba_raw
-
-    demod_05_data = np.loadtxt(filename)
-
-    # Just using some pre-tested values for now for optimizing function, many need changes later.
-    starts, lengths = _findpulses_numba_raw(demod_05_data, 3954307.8, 11.625, 1588.125)
-
-    assert len(starts) == num_pulses
-    assert len(lengths) == num_pulses
-    assert starts[200] == 495955
-    assert lengths[200] == 177
-
-
 class SyncTest(unittest.TestCase):
     def test_sync_pal_good(self):
         blank = 4130000
@@ -151,9 +136,6 @@ def test_sync_pal_noisy(self):
         print("pal noisy")
         test_sync("PAL_NOISY.txt.gz", blank_approx=blank, sync_approx=sync)
 
-    def test_find_pulses(self):
-        test_find_pulses("PAL_GOOD.txt.gz", 458)
-
 
 class ZCTest(unittest.TestCase):
     def test_calczc(self):
@@ -227,10 +209,8 @@ def test_1(self):
         ldd.logger.info("test")
         demod_05_data = np.loadtxt("PAL_GOOD.txt.gz")
 
-        rf_options = {}
-        rf_options["level_detect_divisor"] = 2
         rfdecoder = process.VHSRFDecode(
-            inputfreq=40, system="PAL", tape_format="VHS", rf_options=rf_options
+            inputfreq=40, system="PAL", tape_format="VHS"
         )
 
         data_stub = {}
@@ -241,11 +221,11 @@ def test_1(self):
 
         field = FieldPALVHS(rfdecoder, data_stub)
 
-        _ = rfdecoder.resync.get_pulses(field)
-        blank_level = rfdecoder.resync._field_state._blanklevels.current()
-        sync_level = rfdecoder.resync._field_state._synclevels.current()
-        print("blank level: ", blank_level)
+        _ = field.get_pulses(True)
+        sync_level = field.sync_tip_level
+        blank_level = field.blanking_level
         print("sync level: ", sync_level)
+        print("blank level: ", blank_level)
 
 
 if __name__ == "__main__":

tests/run_integration.sh

@@ -164,7 +164,6 @@ mutation  _export_raw_tbc             "vhs_pal"         --export_raw_tbc
 mutation  _fallback_vsync_ntsc        "svhs_et_ntsc"    --fallback_vsync
 mutation  _fm_audio_notch             "vhs_ntsc"        --fm_audio_notch 10
 mutation  _ire0_adjust                "vhs_ntsc"        --ire0_adjust
-mutation  _level_detect_div5          "svhs_et_ntsc"    --level_detect_divisor 5
 mutation  _nld                        "vhs_ntsc"        --nld
 mutation  _notch_ntsc                 "vhs_ntsc"        --notch 3.58
 mutation  _notch_pal                  "vhs_pal"         --notch 4.43

tests/unit/test_sync.py

@@ -7,16 +7,13 @@
 import lddecode.core as ldd
 import vhsdecode.process as process
 from vhsdecode.field import FieldPALVHS
-from vhsdecode.addons.resync import _findpulses_numba_raw
-
 
 @pytest.fixture
 def pal_rfdecoder():
     ldd.logger = logging.getLogger("test")
     ldd.logger.setLevel(5)
-    rf_options = {"level_detect_divisor": 2}
     return process.VHSRFDecode(
-        inputfreq=40, system="PAL", tape_format="VHS", rf_options=rf_options
+        inputfreq=40, system="PAL", tape_format="VHS"
     )
 
 
@@ -35,35 +32,24 @@ def _make_field(rfdecoder, filename):
 class TestSyncPAL:
     def test_sync_pal_good(self, pal_rfdecoder, data_dir):
         field = _make_field(pal_rfdecoder, data_dir / "PAL_GOOD.txt.gz")
-        pulses = pal_rfdecoder.resync.get_pulses(field)
+        pulses = field.get_pulses()
         assert len(pulses) == 458
-        measured_sync, measured_blank = pal_rfdecoder.resync._field_state.pull_levels()
+        measured_sync, measured_blank = field.sync_tip_level, field.blanking_level
         assert math.isclose(measured_blank, 4133579.15, rel_tol=1e-3)
         assert math.isclose(measured_sync, 3840000, rel_tol=1e-3)
 
     def test_sync_pal_noisy(self, pal_rfdecoder, data_dir):
         field = _make_field(pal_rfdecoder, data_dir / "PAL_NOISY.txt.gz")
-        pal_rfdecoder.resync.get_pulses(field)
-        measured_sync, measured_blank = pal_rfdecoder.resync._field_state.pull_levels()
-        assert math.isclose(measured_blank, 4130360.76, rel_tol=1e-3)
-        assert math.isclose(measured_sync, 3800000, rel_tol=1e-3)
-
-
-class TestFindPulses:
-    def test_find_pulses_pal_good(self, data_dir):
-        demod_05_data = np.loadtxt(data_dir / "PAL_GOOD.txt.gz")
-        starts, lengths = _findpulses_numba_raw(demod_05_data, 3954307.8, 11.625, 1588.125)
-        assert len(starts) == 458
-        assert len(lengths) == 458
-        assert starts[200] == 495955
-        assert lengths[200] == 177
+        _ = field.get_pulses()
+        measured_sync, measured_blank = field.sync_tip_level, field.blanking_level
+        assert math.isclose(measured_blank, 4137794.68, rel_tol=1e-3)
+        assert math.isclose(measured_sync, 3795981.06, rel_tol=1e-3)
 
 
 class TestLevelDetect:
     def test_level_detect_pal_good(self, pal_rfdecoder, data_dir):
         field = _make_field(pal_rfdecoder, data_dir / "PAL_GOOD.txt.gz")
-        pal_rfdecoder.resync.get_pulses(field)
-        blank_level = pal_rfdecoder.resync._field_state._blanklevels.current()
-        sync_level = pal_rfdecoder.resync._field_state._synclevels.current()
-        assert blank_level is not None
+        _ = field.get_pulses(True)
+        sync_level, blank_level = field.sync_tip_level, field.blanking_level
         assert sync_level is not None
+        assert blank_level is not None

vhsdecode/addons/chromaAFC.py

@@ -5,8 +5,8 @@
 from numpy.fft import rfft, rfftfreq
 import lddecode.core as ldd
 from scipy.signal import argrelextrema
-from vhsdecode.linear_filter import FiltersClass
 from vhsdecode.rust_utils import sosfiltfilt_rust
+from vhsdecode.linear_filter import FiltersClass
 
 twopi = 2 * np.pi