How to Watch Half Downloaded Video ?

[poko001]

Generally i can watch half downloaded videos with VLC Player or others, players rebuilding index and allow to watch but some videos are not showing. VLC or others cant open file till end of download. I guess encoder put something end of file and players need that information.

Example file header looks like this ;

ftypisom  isomiso2avc1mp41 freexl€umdat ÿÿÿÜEé½æÙH·–,Ø Ù#îïx264 - core 148 r2597M e86f3a1 - H.264/MPEG-4 AVC codec - Copyleft 2003-2015 - http://www.videolan.org/x264.html - options: cabac=1 ref=4 deblock=1:-1:-1 analyse=0x3:0x113 me=umh subme=9 psy=1 psy_rd=1.00:0.15 mixed_ref=1 me_range=24 chroma_me=1 trellis=2 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-3 threads=32 lookahead_threads=4 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=2 b_adapt=2 b_bias=0 direct=3 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc_lookahead=50 rc=2pass mbtree=1 bitrate=2500 ratetol=1.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 cplxblur=20.0 qblur=0.5 vbv_maxrate=31250 vbv_bufsize=31250 nal_hrd=none filler=0 ip_ratio=1.40 aq=3:1.00 € Òeˆ„ ÛşÃ«æYmóŽ¢¼'u¥õ%øÜÍSÄmx[ìoîÓB:µq·±á:®žŸïŠE‡/ë


I tried many video fixers, repair tools, demuxers non of them worked. Is there any way to watch that kind files ?

[LigH.de]

Rebuilding a proper container is certainly required to provide all the information a splitter needs.

Your header looks like one of the formats in the "ISO Media" container family (may be e.g. MP4, 3GPP or MOV). MediaInfo may tell us a bit more about it. Lost chunks at the end of the file are a quite probable reason that some splitters refuse the playback.

When we know for sure which container variant you have, you can probably use MP4Box to rebuild this container with the partial content, that may require a few additional parameters. Alternatively, you can try to remultiplex your file to MKV with mkvmerge / MKVmergeGUI. And even ffmpeg might be suitable to rebuild a copy with the same container or MKV as target.

[poko001]

I already tried all those softwares, Mediainfo cant give any info, Mp4Box, MKVMerge or others cant recognize too.

[LigH.de]

Then this MP4 style video file was not created in fast loading order for web streaming. There will be so important details in the missing end that players simply don't know the most basic attributes. In this case ... dump it.

[poko001]

I already typed that.

[johns0]

Some shows are compressed in a way so you have to download the whole show,partial files won't play due to the way they were created.

[abolibibelot]

As others have pointed out, a partial MP4 file is unreadable when the index metadata is located at the end (of the whole file, thus missing on the partial one).

Grau Video Repair can at least let you see the begining of such a file. It's not free though – the free version allows to export 50% of the video length. But there's a trick which kinda works : first appending the file with itself once, or twice* (using the command prompt “copy” function), then running this program in free mode. A few links to pages I saved with this program, can't guarantee they're still available and/or relevant (too lazy right now to check them) :
http://grauonline.de/cms2/?page_id=5#download
https://www.reddit.com/r/gopro/comments/16wo2s/how_to_fix_corrupt_video_file/
http://fpvlab.com/forums/showthread.php?8654-How-to-repair-corrupted-MP4-files-from-a-...o.....for-free

* If I remember correctly, copying the file once (thus producing a file twice the size of the original) used to work with version 1.8, but then the author discovered the trick and prevented it, but then it turned out that copying the file twice (thus producing a file three times the size of the original) could still trick version 1.9 into exporting the complete readable length of video. I tried it (version 1.9 -- didn't work with 1.8, don't remember why) with a MP4 video for which a NLE software crashed midway through rendering (I figured I could identify which particular part was causing the issue – it turned out that it was probably a general lack of memory to render a long video with quite complex edits, so I resorted to export it in three parts) ; the resulting video was playable, but still corrupted (severe synchronization issues and other weird stuff), you'll be lucky if you get a video file which is partial but plays flawlessly.
Maybe it works better if you pay the damn thing and use it with no limitation... it depends how important this partial video is to you, or if you often run into this issue.

@ LigH.de

When we know for sure which container variant you have, you can probably use MP4Box to rebuild this container with the partial content, that may require a few additional parameters. Alternatively, you can try to remultiplex your file to MKV with mkvmerge / MKVmergeGUI. And even ffmpeg might be suitable to rebuild a copy with the same container or MKV as target.

Before I tried the aforementioned program I think I had tried all the tools you mentioned (and probably a few others – TSMuxer, MPlayer...), to no avail. It really seems to require a “brute force method”, which regular tools are not suited for.

[LigH.de]

Yes, it depends on which ISO Media chunks are located where. If not only the keyframe index, but even more details describing the content are missing at the end, players may not even know what to expect from the video stream in the beginning.

A last hope may be the fact that there are not only headers in the container, describing basic details of the contained video stream (like width, height, frame rate, etc.), but the contained AVC video stream separately would have its own headers. Players or converters will usually rely on container headers and fail if they don't find any. But if you are able to demultiplex the contained video stream to a raw *.264 file, it may be possible to re-multiplex that because tools supporting raw AVC video as source will know how to interpret the content's headers. But a few details may be missing. I believe that the frame rate is not reliably coded into raw AVC?