EDL Adapter: should author and read timeline::global_start_time attribute rather than source_range.start_time of track

[reinecke]

To Reproduce

import opentimelineio as otio

# Read the screening example from the sample data
timeline = otio.adapters.read_from_file("tests/sample_data/screening_example.edl")

# Note that the source range on the track is offset to make the start timecode work - this assertion passes
assert timeline.tracks[0].source_range.start_time == otio.opentime.RationalTime(value=-86243, rate=24)

# This assertion should pass, but does not because global_start_time is None
assert timeline.global_start_time = otio.opentime.from_timecode("00:59:53:11", 24)

# We should be able to set global_start_time and make the first event record time start at the provided tc
timeline.global_start_time = otio.opentime.from_timecode("02:00:00:00", 24)

# The first event of the written out timeline should have a record start TC of 02:00:00:00
otio.adapters.from_name("cmx_3600").write_to_string(timeline)

Expected Behavior

I would expect that the first event's record start timecode would be set as the global_start_time on the timeline, and that the global_start_time on the timeline would be the first event record time - rather than relying on the source_range on tracks to set the time.

[apetrynet]

Hi TrevorAyl! It seems your comments didn't make it into the comment stream on github. Would you mind summarizing your comments there so we have them recorded?

…

On Mon, Oct 23, 2023 at 12:47 AM TrevorAyl ***@***.***> wrote: Well I've had a little look - seems that the code is written assuming A mode. Not sure if explicitly setting the global_start_time to None is necessary but I added this when the timeline is initialized... class EDLParser: def __init__(self, edl_string, rate=24, ignore_timecode_mismatch=False): self.timeline = schema.Timeline() self.timeline.global_start_time = None Then added the following to the 'add_clip' function to set the global.start_time to be the first record_in the code comes across (I think, I'm not a coder). ` edl_rate = clip_handler.edl_rate record_in = opentime.from_timecode( clip_handler.record_tc_in, edl_rate ) # This should set the record_start to be the first record_in # The whole code does seem to assume A mode EDL # (i.e. so first event number would be first clip added and so earliest record in) if self.timeline.global_start_time is None: # Set the sequence start time self.timeline.global_start_time = record_in elif (record_in < self.timeline.global_start_time) raise EDLParseError( "Record In is less than Record Start: {} < {}" " for EDL event# {}".format( record_in, self.timeline.global_start_time, clip.num )) record_out = opentime.from_timecode( clip_handler.record_tc_out, edl_rate )` Apologies for not doing tests, submitting a pull request or whatever... I haven't learnt that bit yet... Will do that next but probably won't get to it this week so if anyone more knowledgable can confirm I'm in the right ball park ? Thanks — Reply to this email directly, view it on GitHub <#1385 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAIW7YKHMOTWQWFTOPRLNPLYAWPBVAVCNFSM57CH4B42U5DIOJSWCZC7NNSXTN2JONZXKZKDN5WW2ZLOOQ5TCNZXGQZDEMBVGM3A> . You are receiving this because you are subscribed to this thread.Message ID: <AcademySoftwareFoundation/OpenTimelineIO/issues/1385/1774220536@ github.com>

-- -Daniel

[TrevorAyl]

Hi Daniel

Sorry, I deleted them as I realised I'd run before I could walk, and thought I should ponder a little more before going in feet first. If that's not mixing too many metaphors.

I do think there's an underlying issue with the CMX3600 adapter - as it seems to store the track.source_range.start_time as a negative number:
so an initial record in time of "23:00:00:00" is stored as -1.9872e06

                source_range=otio.opentime.TimeRange(
                    start_time=otio.opentime.RationalTime(value=-1.9872e06, rate=24),
                    duration=otio.opentime.RationalTime(value=6, rate=24),
                ),

I wrote a test for this:

    def test_record_in_translation(self):
        tl = otio.adapters.read_from_string(
            'TITLE: enable_test\n'
            '001  Clip001  V     C        00:00:00:00 00:00:00:03 23:00:00:00 23:00:00:03\n'
            '* FROM CLIP NAME:  Clip-001\n'
            '* OTIO TRUNCATED REEL NAME FROM: Clip-001\n'
            '002  Clip002  V     C        00:00:00:03 00:00:00:06 23:00:00:03 23:00:00:06\n'
            '* FROM CLIP NAME:  Clip-002\n'
            '* OTIO TRUNCATED REEL NAME FROM: Clip-002\n',
            adapter_name="cmx_3600", rate=24
        )
        print (tl.tracks[0].source_range.start_time)
        print (otio.opentime.from_timecode("23:00:00:00", 24))

which results in

RationalTime(-1.9872e+06, 24)
RationalTime(1.9872e+06, 24)

I amended cmx3600.py around line 186 as follows,

          if track.source_range is None:
               zero = opentime.RationalTime(0, edl_rate)
               track.source_range = opentime.TimeRange(
                   start_time=zero + record_in,
                   duration=zero
               )

           track_end = track.source_range.start_time + track.duration()

and the numbers from the test are then both positive

RationalTime(1.9872e+06, 24)
RationalTime(1.9872e+06, 24)

but other tests fail. Presumably as there is now a knock on effect down the line.

======================================================================
ERROR: test_edl_round_trip_disk2mem2disk (__main__.EDLAdapterTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/Users/***/Documents/GitHub/OpenTimelineIO/tests/test_cmx_3600_adapter.py", line 325, in test_edl_round_trip_disk2mem2disk
    otio.adapters.write_to_file(timeline, tmp_path)
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/adapters/__init__.py", line 192, in write_to_file
    return adapter.write_to_file(
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/adapters/adapter.py", line 183, in write_to_file
    result = self.write_to_string(input_otio, **adapter_argument_map)
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/adapters/adapter.py", line 274, in write_to_string
    return self._execute_function(
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/plugins/python_plugin.py", line 142, in _execute_function
    return (getattr(self.module(), func_name)(**kwargs))
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/adapters/cmx_3600.py", line 832, in write_to_string
    return writer.get_content_for_track_at_index(0, title=input_otio.name)
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/adapters/cmx_3600.py", line 938, in get_content_for_track_at_index
    content += event.to_edl_format() + '\n'
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/adapters/cmx_3600.py", line 1041, in to_edl_format
    lines = [self.line.to_edl_format(self.edit_number)]
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/adapters/cmx_3600.py", line 1186, in to_edl_format
    'rec_in': opentime.to_timecode(self.record_in, self._rate),
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/opentime.py", line 46, in to_timecode
    else rt.to_timecode(rate, drop_frame)
ValueError: value cannot be negative here

======================================================================
ERROR: test_edl_round_trip_disk2mem2disk_speed_effects (__main__.EDLAdapterTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/Users/***/Documents/GitHub/OpenTimelineIO/tests/test_cmx_3600_adapter.py", line 301, in test_edl_round_trip_disk2mem2disk_speed_effects
    otio.adapters.write_to_file(timeline, tmp_path)
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/adapters/__init__.py", line 192, in write_to_file
    return adapter.write_to_file(
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/adapters/adapter.py", line 183, in write_to_file
    result = self.write_to_string(input_otio, **adapter_argument_map)
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/adapters/adapter.py", line 274, in write_to_string
    return self._execute_function(
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/plugins/python_plugin.py", line 142, in _execute_function
    return (getattr(self.module(), func_name)(**kwargs))
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/adapters/cmx_3600.py", line 832, in write_to_string
    return writer.get_content_for_track_at_index(0, title=input_otio.name)
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/adapters/cmx_3600.py", line 938, in get_content_for_track_at_index
    content += event.to_edl_format() + '\n'
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/adapters/cmx_3600.py", line 1041, in to_edl_format
    lines = [self.line.to_edl_format(self.edit_number)]
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/adapters/cmx_3600.py", line 1186, in to_edl_format
    'rec_in': opentime.to_timecode(self.record_in, self._rate),
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/opentime.py", line 46, in to_timecode
    else rt.to_timecode(rate, drop_frame)
ValueError: value cannot be negative here

======================================================================
ERROR: test_edl_round_trip_with_transitions (__main__.EDLAdapterTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/Users/***/Documents/GitHub/OpenTimelineIO/tests/test_cmx_3600_adapter.py", line 621, in test_edl_round_trip_with_transitions
    otio.adapters.write_to_file(timeline, tmp_path)
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/adapters/__init__.py", line 192, in write_to_file
    return adapter.write_to_file(
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/adapters/adapter.py", line 183, in write_to_file
    result = self.write_to_string(input_otio, **adapter_argument_map)
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/adapters/adapter.py", line 274, in write_to_string
    return self._execute_function(
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/plugins/python_plugin.py", line 142, in _execute_function
    return (getattr(self.module(), func_name)(**kwargs))
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/adapters/cmx_3600.py", line 832, in write_to_string
    return writer.get_content_for_track_at_index(0, title=input_otio.name)
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/adapters/cmx_3600.py", line 938, in get_content_for_track_at_index
    content += event.to_edl_format() + '\n'
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/adapters/cmx_3600.py", line 1041, in to_edl_format
    lines = [self.line.to_edl_format(self.edit_number)]
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/adapters/cmx_3600.py", line 1186, in to_edl_format
    'rec_in': opentime.to_timecode(self.record_in, self._rate),
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/opentime.py", line 46, in to_timecode
    else rt.to_timecode(rate, drop_frame)
ValueError: value cannot be negative here

======================================================================
ERROR: test_reels_edl_round_trip_string2mem2string (__main__.EDLAdapterTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/Users/***/Documents/GitHub/OpenTimelineIO/tests/test_cmx_3600_adapter.py", line 888, in test_reels_edl_round_trip_string2mem2string
    otio_data = otio.adapters.write_to_string(timeline, adapter_name="cmx_3600",
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/adapters/__init__.py", line 213, in write_to_string
    return adapter.write_to_string(
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/adapters/adapter.py", line 274, in write_to_string
    return self._execute_function(
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/plugins/python_plugin.py", line 142, in _execute_function
    return (getattr(self.module(), func_name)(**kwargs))
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/adapters/cmx_3600.py", line 832, in write_to_string
    return writer.get_content_for_track_at_index(0, title=input_otio.name)
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/adapters/cmx_3600.py", line 938, in get_content_for_track_at_index
    content += event.to_edl_format() + '\n'
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/adapters/cmx_3600.py", line 1041, in to_edl_format
    lines = [self.line.to_edl_format(self.edit_number)]
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/adapters/cmx_3600.py", line 1186, in to_edl_format
    'rec_in': opentime.to_timecode(self.record_in, self._rate),
  File "/Users/***/Documents/GitHub/otioenv/lib/python3.9/site-packages/opentimelineio/opentime.py", line 46, in to_timecode
    else rt.to_timecode(rate, drop_frame)
ValueError: value cannot be negative here

Presumably the timeline.global_start_time should be the 'sequence start' for an NLE and the track[n].source_range.start_time should be the start time for a particular track in that timeline.

As far as EDLs go they can only have one video track per EDL (I guess keys are two tracks but I don't think they are used much or implemented in this adapter) - but sometimes each video track is exported as it's own EDL - and the sequence start would be the earliest record in from those EDLs.

I'll have a further look when I get the chance and see if I can figure out more. Hopefully without breaking too much or making a mess.

I'm very much learning here - so feel free to point out any errors or easier ways of doing things.

Trevor