Is there a point in using QuickTime Player's 'maximum' quality for streaming Hi8 analog tapes?

A couple things on clip size. The only choice for iMovie 5 is to have a clip per scene or not, and of course that is only for Digital8. For Hi8 or for Digital 8 without "clip per scene" enabled, the clip size will be 1hr. I can't find any way to control that.

If I do choose "clip per scene", what does it take to later combine multiple clips into one clip, and keep in the DV format so there is no loss of quality, or in general can you edit a DV clip and save as DV? iMovie doesn't seem to support DV as an output type. VLC seems just plain broken on macOS. I can't figure out how to combine multiple clips. The "convert" feature doesn't even allow you to choose multiple clips to combine. On YouTube it shows how to do combine clips on Windows using "Add multiple...", but that doesn't seem to exist on macOS. I have yet to find an explanation on YouTube on how to do something with VLC that actually worked as shown, as the demonstration are always on Windows.

iMovie doesn't seem to support DV as an output type.

I should clarify. iMovie 10 doesn't seem to export DV. iMovie 5 on my G4 does, although I wouldn't want to rely on this as a future way of merging or editing DV clips since this hardware is already very old.

Matti Haveri wrote:

cjp987 wrote:

With 4:3 NTSC scale 720x480 to 648x480 and then crop to the final 640x480.

I understand you are trying to crop the artifact at the bottom of the image

No, that relates to converting rectangular DV pixels to square pixels which computer monitors use. If that is not done, then circles will not be circles but ovals in the output.

Ignoring the artifact issue, I thought going from 720x480 to 640x480 was how the scaling (rectangular pixels to square) was normally done. Then I thought with the above you were suggesting how to both scale and crop the artifact at the bottom. If you only scale to 648, isn't the pixel still somewhat rectangular, but just not as much? If you don't fully scale down the horizontal down to 640, don't you need to scale up the vertical to make up for it. For example, maybe something like 648x486 to get the 4:3 ratio, and then clip to 640x480 to remove the artifact from the bottom, if removing 6 pixel lines is enough to do so.

Matti Haveri wrote:

Just pause the import so a new clip will be created when you re-start import. You might want to rewind the tape slightly before starting re-import so the are no skipped frames in between.

I have a bout 40 hours of tape to go through. I don't have the time to monitor, so I'll probably just go with the 1hr clips. Or maybe I can find a copy of iMovie 4. I think that was the version I used to create the 9m clips back in 2003.

While you are at it I'd recommend renaming the imported .dv clips with a date in YYYY-MMDD-hhmm-ss.dv format (1998-0601-1200-00.dv etc, including seconds. Just use your best guess about the old date) so it is then easier to add metadata dates and other metadata to the exported .mp4 movies.

My tapes have labels with date ranges, generally anywhere from 3mo to 9mo, so I just create a folder with the date range as the name and store all the clips in it. I don't really have any plans to piece together a movie with clips from different tapes. Right now this is really just an archival task, and maybe after that generating an .mp4 movie per tape. For this step at most I would do edits to get rid of things like the camera recording for 30 minutes while sitting on the floor of the car. Unintentional lengthy recordings happened way too often. Actually this is something I'd like to edit out of the .dv versions of the clips.

Regarding using "clip per scene" or not, I think I'll use it. I played around with ffmpeg. Once you figure it out, it's pretty easy to combine all the clips into one giant clip. So I'll just capture in "clip per scene" mode, use ffmpeg to make a single file, and archive both. Whoever is doing video editing can decide which one they prefer.

cjp987 wrote:

Regarding using "clip per scene" or not, I think I'll use it. I played around with ffmpeg. Once you figure it out, it's pretty easy to combine all the clips into one giant clip. So I'll just capture in "clip per scene" mode, use ffmpeg to make a single file, and archive both. Whoever is doing video editing can decide which one they prefer.

One issue I have with doing this is that I'm getting the following error from ffmpeg:

[dv @ 0x7f90f2404f80] Invalid sample rate 32000 for audio stream #0 for this video profile, must be 48000.

I found that using the -an option to "disable audio" fixes this. I'm still getting audio in the output .dv file, which is a good thing, but using this option still leaves me with an uneasy feeling. I first tried "-ar 48000", but that didn't. I then noticed "-an" in the help output and decided to give it try. Googling for "ffmpeg" and "-an" pretty much turns up nothing. And just for reference, there is also the following in the output before the error:

Input #0, concat, from 'filelist.txt':

Duration: N/A, start: 0.000000, bitrate: 30819 kb/s

Stream #0:0: Video: dvvideo, yuv411p, 720x480 [SAR 8:9 DAR 4:3], 28771 kb/s, 60k fps, 29.97 tbr, 60k tbn

Stream #0:1: Audio: pcm_s16le, 32000 Hz, stereo, s16, 1024 kb/s

Stream #0:2: Audio: pcm_s16le, 32000 Hz, stereo, s16, 1024 kb/s

So obviously 32 kHz stems from the original camcorder setting and tapes

and you might leave it as such, although using 32 kHz, 12-bit audio

might make the audio out of sync as well as other audio glitches.

It looks like by default my camera recorded in 12-bit:

I'm not sure what is meant by "two stereo sounds" and "one stereo sound". I still don't get why using "-an" makes the error go away. I haven't noticed any audio issues yet, but I'll check a look closer.

I have been wary joining movie files because they should all have exactly the same codec and codec parameters but your .dv files imported via the same workflow should be the same.

Yes. I'm always joining the multiple .dv clips that are created when doing a single import of a tape, and the entire tape was filmed using the same camera (I read that recording on a single tape using different cameras can cause problems).

A few multimedia containers (MPEG-1, MPEG-2 PS, DV) allow one to concatenate video by merely concatenating the files containing them with the humble cat command (the output is essentially the same as with MPEG Streamclip):

cat input1.dv input2.dv input3.dv > joined.dv

I'll definitely give that a try.

BTW, I could really use a video editor that allow me to edit the DV clip (namely, remove sections of video from the clip), and then re-export as DV without decoding/encoding the entire clip (but possibly doing so for a few seconds around the edit). ffmpeg can accomplish that, but you need to specify the time code of where to split the clip, which I imagine will take some trial an error before getting it just right. And then of course you will need to split again at the end of the section of the clip you want to edit out. So then you have 3 clips and you throw away the middle one, and then concat the two remaining clips. Rather laborious, especially if there are multiple edits you want to make.

It looks like by default my camera recorded in 12-bit:

I should clarify that statement. The man page image I showed is for my D8 camera, but I have both Hi8 and D8 tapes. They both seem to have this 32000 Hz issue when playing off the D8 camera. I'm not really sure how the Hi8 tapes were recorded as I don't have the camera anymore. For both the converted Hi8 tapes and the D8 tapes, QT Player inspector says the following about the audio:

Linear PCM, 16 bit little-endian signed integer, 32000 Hz

So it 16-bit, but 32000 Hz???

Regarding audio bit-rate, I'm not too clear what you are suggesting I do for my situation. Using ffmpeg with -an at least lets me work with the .dv files (concat them without the audio error), although I'm still not clear on why -an works, or possible negative side affects of using it.

Sound quality is not that important to me (these are just home movies done with a consumer camcorder). Just as long as I can hear what people are saying and there aren't bad audio glitches, I'm not too worried. I'm okay with the sound quality I've gotten so far, but still need to pay closer attention to it to see if there are issues I hadn't noticed before.

If you think there is something I can do with ffmpeg when concatenating .dv files to improve the audio situation, please let me know which options I should use. As mentioned earlier, -ar doesn't seem to have any impact. Also let me know if any special handling of the audio will be needed when eventually converting to other formats like h.264.

Thanks!

Just to be clear on the ability of MPEG Streamclip when dealing with DV, you mentioned using it to concat, but I was wondering if it could be used to edit. Specifically, to remove a section of a DV clip, and then re-export as DV (with no loss except at the edit point). I can do this with ffmpeg, but it's very clumsy to do from the command line instead of a GUI where I would just click on the start and end points that I want to remove.

The "DV movie" files I have are about 25gb per hour of video.

[CORRECTION] Looks like those are 2 hours tapes. Didn't realize that I have a mix of 1hr and 2hr tapes.

Matti Haveri wrote:

If you are fluent in using ffmpeg...

Well, as fluent as one can be after toying around with it for a couple

of hours. I'll make note of your recipe for future usage. Thanks!