Error trimming MOV (QuickTime) files. Can anybody advise me what i'm doing wrong

[djboshh]

Error trimming MOV (QuickTime) files. Can anybody advise me what i'm doing wrong?

I'm new to Avidemux & I don't know much about video formats and so any help is appreciated.

MediaInfo tells me my video file/s are MPEG-4 (QuickTime) with Audio of 256Kbps, 16.0 KHz, 16 bits, 1 channel, PCM (Big/Signed).

What i want to do is to lossless trim the start & ends of my video clips. I understand that all i need to do in Avidemux is to locate the file, mark the new start and end points, leave the Video & Audio drop down box on 'Copy' (to keep it lossless) and then to make sure the Format drop down box matches that of your file. Now, there is no option in the format drop down box for .MOV (QuickTime) and so i assume that i should choose the MP4 option (like MediaInfo states). I then attempt to save my new file, & I understand (from reading these forums) that i have to include the file extension myself in the save window and so i assume my files are classed as MPEG-4 and so I use the .mp4 extension. However, when i do this i get an error message saying invalid audio stream detected.

It's obvious that i'm doing something wrong. Can anybody advise me what it is please and how to do it right?

[Agent_007]

Can you share us one problematic .mov file?

[djboshh]

Thanks & yes

P.s The MOV file is untouched straight from my Camera (Panasonic Lumix DMC-GF3). Also, i have the latest version of K-lite codec pack installed on my PC.

http://www.mediafire.com/?azw13nq8euaa5p0

[styrol]

However, when i do this i get an error message saying invalid audio stream detected.

What compatibility is concerned you shouldn't put PCM audio in MP4 container. Such private streams are only supported by some software (mainly QuickTime). Apple uses the MOV format for this.

For MP4 container (which is MOV based) AAC codec is the best choice when compatibility matters.

Other audio streams like MPEG-1 Layer 3 (MP3) or AC-3 are sometimes to be found in MP4 containers. While MP3 is supported by MPEG, AC-3 is not.

So I suggest you use: container format: MP4, video codec: COPY, audio codec: AAC
or
container format: AVI, video codec: COPY, audio codec: MP3

If video track is MPEG-4 ASP smart edit should be supported (you don't have to cut at keyframes).

[djboshh]

Thanks for your 2 suggestions of:

1) container format: MP4, video codec: COPY, audio codec: AAC
or
2) container format: AVI, video codec: COPY, audio codec: MP3

The 1st suggestion didn't work, as i had an error code of "[BuildChain] Encoder initialization failed - Not activated, make sure number of channels and bitrate are compatible with encoder!"

The 2nd suggestion worked but took over a minute to encode! My question is therefore: Is it still lossless?

I have to admit that i don't really understand about containers etc, how formats can be swapped, and how it all works. I feel like i would like to understand it so i know what is going on. Any suggestions?

[Jan Gruuthuse]

Perhaps this can give you some inside: Guide to encoding types _{<- click}

[styrol]

The 2nd suggestion worked but took over a minute to encode! My question is therefore: Is it still lossless?

No, it's not what audio track is concerned. MP3 is lossy codec. I've downloaded your source video, your video track is not MPEG-4, it's plain Motion JPEG (Apple Photo JPEG), so use:

Container format: AVI; video codec: Copy; audio codec: PCM; Filters: Resampling (Hz): 16000

You might try copy mode for audio, but Avidemux often has problems with PCM untouched (meaning Players like VLC, MPlayer, QuickTime Player won't play audio track in this case).

[djboshh]

The 2nd suggestion worked but took over a minute to encode! My question is therefore: Is it still lossless?

No, it's not what audio track is concerned. MP3 is lossy codec. I've downloaded your source video, your video track is not MPEG-4, it's plain Motion JPEG (Apple Photo JPEG), so use:

Container format: AVI; video codec: Copy; audio codec: PCM; Filters: Resampling (Hz): 16000

You might try copy mode for audio, but Avidemux often has problems with PCM untouched (meaning Players like VLC, MPlayer, QuickTime Player won't play audio track in this case).

How interesting & now things are making sense i think.

I had made a mistake somewhere then and i think i may know where i made my mistake. I used MediaInfo to tell me what my video clips are, and it told me they were "MPEG-4 (QuickTime)", but in looking at MediaInfo again and more closely (and now i know a bit more about formats and codecs) i think it must of been referring to the format being MPEG-4 rather than the video codec. MediaInfo does says the codec is JPEG and so i think your spot on. Am i right in saying there is a format called MP4 and also a codec called MPEG4, and perhaps i've been confused by that? I'm new to video trimming and already feel i know 100 times more today than what i did yesterday. Thanks so much for your help.

[styrol]

Am i right in saying there is a format called MP4 and also a codec called MPEG4

Yep. But your video is not MPEG-4 in any case. The only link is the container format MOV. The MPEG-4 file format specification was created on the basis of the QuickTime format specification, or in other words, MP4 is mainly based on the QuickTime file format (MOV). So maybe MediaInfo is referring to that.

[djboshh]

Thanks again for all your help - much appreciated 

[styrol]

Format : MPEG-4
Format profile : QuickTime
Codec ID : qt
File size : 59.9 MiB
Duration : 17s 0ms
Overall bit rate : 29.6 Mbps
Encoded date : UTC 2012-03-13 14:41:27
Tagged date : UTC 2012-03-13 14:41:27
Writing library : pana

Format: MPEG-4 ââ,¬â€œ I think this is a inappropriate labeling of the Panasonic writing lbrary (or of MediaInfo).

[djboshh]

Just a thought:

I'm absolutely new to video editing (including lossless trimming) & Avidemux too. I found the understanding of the basics and principles obviously hard and really got the impression that the help tutorials for Avidemux were geared towards those who at least knew something about the subject already , & I especially found the concepts of things like container formats, codecs, how and why certain formats can be exchanged & repackaged (and why some can't) quite hard to realise and understand. I'm thinking that it would of been great to have had a help section just for absolute beginners who know nothing about it all, with the basic essential concepts explained, and written in a way that an absolute beginner can understand. It would be a shame if absolute beginners were put off by how complex it can seem at 1st and never got to realise how great & powerful this piece of software really is.

Maybe i could start a new post on the subject?

[styrol]

Your certainly right. There is a wiki, but yes, it's not for "dummies": http://www.avidemux.org/admWiki/doku.php

You may read here.

You may repost here: http://www.avidemux.org/smf/index.php?board=19.0

[djboshh]

Ok, Done 

Avidemux instructions for "dummies" :

http://www.avidemux.org/smf/index.php?topic=10420.0

[djboshh]

I just wanted to add: The more i play around with Avidemux the more i absolutely love it