Can anyone suggest a program to edit iphone video on a PC?

[l33tmeatwad]

It's not even about quality... if keyframes are too far from each other and you need to reverse speed/do heavy time alterations/massive overlays/whatever, the seek time will hit on you even with a good cpu, because you're limited by the hard drive speed too, and not just by the processing power.
Depending on what file they are using for editing, there may be literally hundreds of frames between keyframes, and that won't be fun to reverse or seek through.
Once upon a time I used to load .avs directly in premiere to edit to save space. With time I realized why people suggested lossless clipping on my own.

Then again with iphone footage it likely has plenty of keyframes (prolly 24 frame GOPs or something like that), so it shouldn't be too bad...

But anyway, when I say intra only I don't even necessarily mean lossless. Even h.264 or whatever else. Just... only keyframes, or possibly 1 or 2 P frames per GOP tops.

Well, if you are going from lossy to anything else I would only suggest lossless, but I get your point. Again, it really depends on what software you are using, the footage itself, and what you plan on using it for (which was my point), as I know some (like Premiere) handle it quite nicely and you can generate previews that the software will read from. Additionally, I've found that teaching people about recontainering not only gives them a better understand of what containers are, but it also tends to nix a lot of bad habits as well (such as reencoding footage with x264 again to an MP4 container, or worse, encoding footage to older MPEG-4 codecs).

Again, I didn't get the feeling the original poster really wanted to do anything extensive with the footage so that is the main thing behind my suggestion. Generally if I catch that the editor wants to edit something intensive (like an AMV) then I will usually stress the advantages of converting the video the lossless AVIsto work with first, but I will also give the option to choose. Some have to learn on their own (as I see you did as well), so I give them the power to chose what they want with options.

Not trying to start a war, just giving my thoughts on the matter

[mirkosp]

Yeah, that's fine. In general I'm concerned about this because... I didn't enjoy what I had to go through back then, so now I really stress on it just so I can spare other people from making my same mistake from back then.

[l33tmeatwad]

Yeah, that's fine. In general I'm concerned about this because... I didn't enjoy what I had to go through back then, so now I really stress on it just so I can spare other people from making my same mistake from back then.

Haha, I hear ya...I've been doing this kinda stuff for so long that I've had my share of "doing it the hard way" as well. Having taught people over the years (not just tech based stuff) I've learned that some people need to be told exactly what to do, while others do not want that at all, but would rather be given options so they can "learn" or "figure it out" themselves. There are also those that only want to know how they envisioned doing it and will ignore all advice that isn't the direct answer that they are looking for. I try to keep a balanced approach so I can at least point people in a better direction, even if it's not the BEST option, while usually making mention that there are better ways.

[Mister Hatt]

Ah... what? Avisynth doesn't have a default colourspace for loaded clips, it defers to the source plugin. Also, MOV is a subset of MP4 so it has to work unless the demuxer has incomplete MP4 support to begin with.

As far as seek times etc, the biggest limiting factors are HDD spin speed and CPU cache size, not the CPU speed in itself. Large files or poorly spaced keyframes hit on HDD limits due to buffers not being large enough and seeks not being fast enough, so lossy but intra-only AVC is a good choice if it compresses better than lossless. Too many reference frames and other complicated bits and bobs have inefficient decoding thanks to limited CPU cache so going intra-only and not relying on references improve speed in that regard, even on something like an i3. Of course that depends on the decoder at hand as well.

[l33tmeatwad]

Ah... what? Avisynth doesn't have a default colourspace for loaded clips, it defers to the source plugin.

You are correct, it does not have a default colorspace for the loaded clips and does use the colorspace based on the information referred to it by the input plugin (which reads the colorspace information from the video file itself). That said, it does have a default way of reading the color information of YV12 footage when converting to RGB, which is by using the Rec.601 color matrix. This information is in the AviSynth documentation...I'm surprised someone as well versed in this as you are happened to overlook this, but to be fair it's not easy to notice most of the time as it does not throw the overall hue way off or anything. Here is an example using HD footage (resized in Photoshop after taking the screenshots):

Also, MOV is a subset of MP4 so it has to work unless the demuxer has incomplete MP4 support to begin with.

What should be the case is not always how things actually are. It depends on how the software is handling the containers, sometimes plugins don't always support what you think they should. Just because MP4 was developed based on MOV does not mean software that supports MP4 will by default support the use of or handling of a MOV container. Additionally, the way in which a particular software handles containers can control how the footage performs in the editing software. This can cause one type of container to have a significant amount of lag and/or other issues compared to another even with the same exact video information inside of them.

As far as seek times etc, the biggest limiting factors are HDD spin speed and CPU cache size, not the CPU speed in itself. Large files or poorly spaced keyframes hit on HDD limits due to buffers not being large enough and seeks not being fast enough, so lossy but intra-only AVC is a good choice if it compresses better than lossless. Too many reference frames and other complicated bits and bobs have inefficient decoding thanks to limited CPU cache so going intra-only and not relying on references improve speed in that regard, even on something like an i3. Of course that depends on the decoder at hand as well.

Exactly, it depends on a lot of factors, and having used iPhone footage to do simple edit before it is not going to be a nightmare. Again, not trying to start a war here, but it's rather deceptive to not give possible options because those options aren't good for COMPLEX editing, yet are perfectly fine for simple tasks.

[Mister Hatt]

Actually the source filters can pass the colour matrix as well. To be fair, I was implying the matrix when I said space (because really, they're the same), but I suppose it does depend on which filter as to how correctly they do it. DSS is known for getting it wrong, along with all the hardware decoder ones last I checked.

As far as containers go, it really boils down to "am I using Sony Vegas or any other program that actually cares about the extension?".

[l33tmeatwad]

Actually the source filters can pass the colour matrix as well. To be fair, I was implying the matrix when I said space (because really, they're the same), but I suppose it does depend on which filter as to how correctly they do it. DSS is known for getting it wrong, along with all the hardware decoder ones last I checked.

The color matrix is used to specify how the color information is calculated and stored and only comes to play when converting to RGB from YV12 and vice versa. AviSynth does not know the different between Rec.601 and Rec.709, but that is irrelevant when it comes to processing the video with its existing colorspace. The only reason you would have an issue with the colorspace being messed up through an input filter would be if it converted the footage to RGB while bringing it in, otherwise the color matrix would not be affected at all. Again, just read the documentation, you need to specify the Rec.709 color matrix whenever you convert HD footage from YV12 to RGB in AviSynth or it will be converted improperly, no matter what filter you are importing with!

Actually the source filters can pass the colour matrix as well. To be fair, I was implying the matrix when I said space (because really, they're the same), but I suppose it does depend on which filter as to how correctly they do it. DSS is known for getting it wrong, along with all the hardware decoder ones last I checked.

Vegas is pretty bad about that kind of stuff, but they are most likely not the only editing software that has issues with these kind of things. There is plenty of cheap software out there that do not handle things as they should.

[youtuber]

The iphone video format is mp4 h264, there are plenty software could edit this kind of format. Like xvid/divx, smartpixel.