DPX image sequence is opened as an A/V file 1 frame long

[tin2tin]

FFplay(ffmpeg) opens and plays the dpx img seq correctly, so is there a misreading in MLT of what dpx files are?

For quick testing I've uploaded a file with an dxp and a png img seq here: http://we.tl/b1rVSvf1R5

MediaInfo of a dpx file:
General
Complete name : C:\Users\user\Desktop\EFC test\DPX\Ny_25_fps-0001.dpx
CompleteName_Last : C:\Users\user\Desktop\EFC test\DPX\Ny_25_fps-0026.dpx
Format : DPX
Format version : Version 2
File size : 309 MiB
Writing library : Lavc53.9.0

Video
Format : DPX
Format version : Version 2
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Bit depth : 16 bits
Scan type : Progressive
Compression mode : Lossless
Stream size : 309 MiB (100%)
Writing library : Lavc53.9.0
Color primaries : Linear

The img seq files was created with ffmbc/Eyeframe Converter from an Avisynth file.

[ddennedy]

DPX image sequences are not supported at this time. Limitations are not bugs, and I do not use this to track feature requests.

[ddennedy]

Basically, we do not use FFmpeg for most image and image sequence support; we use Qt QImage and have our own image sequence handling. FFmpeg having good image sequence support is a somewhat recent thing. At some point I need to investigate switching to that or having better support for that.

For now there is a workaround. Open the first image, then choose File > Open Other > Network. You will notice the file path to that first DPX image is already filled in in the URL field. Really, this tab lets you input any MLT resource specifier. Change the numeric part of the file name into a pattern, e.g. Ny_25_fps-%04d.dpx. Press OK and Shotcut starts to play it, but now it thinks it is a Live source and provides no seeking or trimming. Choose File > Save and save a virtual clip as MLT XML. Now, open the MLT XML file and it has a duration and you can seek, scrub, and use it as a clip.

[ddennedy]

Actually, seeking and scrubbing on DPX image sequence is not working good and not reliable. Oh well.

[ddennedy]

I decided to re-open this. This bug fell into a gray area for me, and I could not decide how to handle it for a while. If there is something in our technology stack that is integrated but does not work correctly and can be expected to work correctly within Shotcut/MLT constraints, then it should be a bug even if I have never used it or know anything about it. I do not have to feel like I am obligated to fix it within a certain time or that I am even obligated to fix it at all or fix it for free. Someone might just want to check on status and track it, or they might be wanting to help and looking for things to do.