Video upload unsuccessful on iOs [share extension does not compress the file]

tmattei · August 20, 2026, 2:55pm

Hi all and sorry for not following the scheme provided but my question requires a different wording.

A friend of mine who uses the iOs client tried to send a video on a group chat we’re in.

The video failed to load. I can see a text bubble with a “Download” button (not working) and the indication that the video is around 123 MiB.

She then sent the same video in a Whatsapp group, and from there I see that it’s a very ‘normal’ 1:08 minute video and WA actually compressed it to be around 6.2 MB.

I know Delta also compresses sent videos, but maybe something’s going wrong on the sender’s side and it didn’t get compressed? If so, where is the relevant setting in the iOs version? (I can find it in the Android version under the “Chat” menu but I don’t know if it’s the same option under iOs)

Thank you for helping!

Tiziano

link2xt · August 20, 2026, 3:06pm

There seems to be a relevant issue:

tmattei · August 20, 2026, 3:17pm

Wow, thank you for the quick reply.

Does this mean that if my friend attaches the video from inside the message composer in the chat, instead of using the global share feature, the upload will likely work?

link2xt · August 20, 2026, 3:38pm

I don’t have iOS, but at least it looks like the code to do the compression is there:

github.com/deltachat/deltachat-ios

deltachat-ios/Chat/ChatViewController.swift

7332bcad3


      
          func onVideoSelected(url: NSURL) {
              DispatchQueue.main.async {
                  let url = url as URL
                  let progressAlertHandler = ProgressAlertHandler()
                  progressAlertHandler.dataSource = self
                  progressAlertHandler.showProgressAlert(title: nil, dcContext: self.dcContext)
                  DispatchQueue.global().async {
                      url.convertToMp4(completionHandler: { [weak self] url, error in
                          _ = DcUtils.generateThumbnailFromVideo(url: url)
                          DispatchQueue.main.async { [weak self] in
                              if let url, !progressAlertHandler.cancelled {
                                  self?.stageVideo(url: (url as NSURL))
                                  progressAlertHandler.updateProgressAlertSuccess()
                              } else if let error {
                                  progressAlertHandler.updateProgressAlert(error: error.localizedDescription)
                              }
                          }
                      })
                  }
              }
          }

tmattei · August 22, 2026, 8:54pm

Update: I’ve asked my friend who uses the iOs client to send a video to the group using the “attach” icon within the chat. It didn’t work either. The video is around 24 MiB. It didn’t get compressed and it didn’t get uploaded (she has the red (!) and we see the broken “Download” button).

ian · August 22, 2026, 9:34pm

Usual limitations of email will cause attachments exceeding about 20MB to fail to some destinations, hence you should not send such large files directly.

link2xt · August 23, 2026, 12:09am

If WhatsApp managed to compress it to 6 MB instead of 24 MB, maybe DC can improve the compression somehow, e.g. for the cases when the video is large choose worse quality.

tmattei · August 23, 2026, 6:52am

I may have expressed myself poorly: the 24 MiB video is a different one. In fact it’s a 12-seconds video, that’s why it’s only 24 MiB. It didn’t get compressed at all.

tmattei · August 23, 2026, 7:00am

Yes, but that’s what compression is for, isn’t it? In fact those are very short (10 to 60 seconds) videos that are very common in group chats. And when using the Android app I have no trouble sending even longer videos directly, so it should work on the iOS client, too. BTW I’ve already posted the “Sharer” mini-app and suggested the group members to use it if they have any trouble, but this shouldn’t be the norm.