Friday, November 28, 2014

Lossless MKV to MP4 (thanks, ffmpeg)


The following all still applies and is sound advice, but you can perform a simple container switch (I think the technical term is demux and remux) or lossless conversion (no re-encode) using VLC, which is pretty common among people who want to view media. I won't re-invent the wheel, and you can google "mkv to mp4 vlc" to see videos on how to do this, but you are basically opening VLC and choosing file>convert/save, then picking the source file (mkv) and clicking convert/save, then select the 'tools' by the profile dropdown and set 'encapsulation' to mp4/mov, and audio and video to 'keep original.' Then just click save and set your destination file and do it.

Keep in mind that mp4 files are, arguably, a little more well received as apple devices can play them and they are a little more friendly for web streaming. That said, I prefer the mkv container as it allows multiple subtitle tracks and allows various codecs such as . The mp4 container, I believe, is only supposed to work with older mpeg or avc/h.264 encoded video and AAC encoded audio.

And soon enough we can re-visit with HEVC/VP9/Daala thoughts...

A long time ago, I wanted to "extract" my video and audio from a mkv and put them into a html5 video friendly .ogv file/container. I wrote about it here.

This is a little more of an update to that post than a new idea, but I was dissapointed at the search results when I googled "lossless mkv to mp4" and hope this may be of some assistance. It probably won't. Here's hope.

It really isn't bad. If you want to be thorough, install MediaInfo and verify the audio code and video codec are compatible. I'm not sure what mp4 accepts, but AVC/h.264 for video and aac for audio seem to be the most common codecs. Technically, you could copy the video and recode the audio if that was needed for your situation. The code would need little modification.

Install ffmpeg. Get the package for your OS (i'm using Windows), then extract it. It doesn't have to install, so pay attention to where you extract to.

Next, open cmd (search from the start-menu search) and browse to where you extracted ffmpeg. Try using 'tab' to auto complete from cmd. It saves tons of time. Tab multiple times to cycle through potential completions.

Type the following, using the video (full location input and output --fun, I know!) for input.mkv and the name you want as output.mp4: C:\videdit\ffmpeg\bin>ffmpeg -i c:\Users\nchapman\Videos\christianeatingwackyburger.mkv -codec copy c:\Users\nchapman\Videos\newchristianeatingwackyburger.mp4

Hope this helps! You can use -acodec mp3 -vcodec copy or something crazy if you prefer.

Also, you can encode all files in a directory by saving this to a .bat file (then, drag a .mkv file onto it):
for %%a in ("*.mkv") do ffmpeg.exe -i "%%a" -vcodec copy -acodec copy "%%~na .mp4" pause

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Monday, August 11, 2014

I Replaced my Old Nikon D70 with a Used Nikon D3100

But, Why?

I had two Nikon D70 cameras which, over the past couple of years, became increasingly unusable. Both had been purchased second-hand on ebay in 2005 or 2006 at reasonable prices. One came with a 18-70mm and the other a 28-80mm and a 70-300mm. I prefer the 18mm, despite the distortion, for the wider angles it provides on my DX sensor, so rarely used the 28mm zoom. 2 years ago, I was given a 50mm 1.8 and LOVE it!

First Camera

I shot the transit of venus in late 2012 with a 70-300mm and not enough filters and, seemingly, damaged my shutter. The camera stopped working properly shortly after, so that is my best guess. It still shoots up to 1/60th of a second shutter speed, but nothing higher (just black images) and has trouble syncing with the flash (related)...etc, so very limited in use (only high aperture shooting up to 1/60th frames per second -- fine for tripod landscape shooting, I guess).

Second Camera

The other has no excuse other than the wear and tear I exposed it to for the past 8 years. I use my cameras to get shots, which means on the beach, in the ocean, whilst raining, etc. Sometimes my kids run around and use them as bludgeoning devices. All the cameras get in return is a lens/sensor cleaning occasionally and maybe a UV filter on the lenses to offer some type of safeguard (well, I use lens caps when I can). One day, half-way through shooting my son at the park, it made a chunking noise (much slower and louder than the usual mirror flip/shutter release speed) and seemed to fail mid mirror flip. Since then it flashes 'Err' on the display and won't successfully shoot at all.

Hello New Old D3100

I bought a D3100 just in time for vacation. Literally, it arrived the day before we left. I really like it. I kinda want a 18-55 VR lens that usually comes with them, but may get it separately later. I have almost all positive things to say. There is a slight learning curve which reading reviews and the guide will help alleviate, but I was able to do most everything I wanted immediately and with one less rotating dial than I was used to (for aperture/f-stop adjustments, you use the rear dial when on aperture priority or hold a button and rotate the rear dial when on other modes that allow aperture adjustments -- the D70 has a rear for the shutter and front for the aperture). The ISO can easily be adjusted during shooting, too. My only complaints are as follows:
  • *No IR receiver -- doesn't work with my cheap remote
  • Internal flash doesn't work as commander for my SB600 -- I don't use this feature often, but like being able to play around with it occasionally
  • *Doesn't auto-focus with my 50mm/1.8 or 70-300mm -- pretty much only lenses with a m/ma selector ON THE LENS can be auto-focused by this camera. This was an oversight on my part, and was clearly documented.
  • The video doesn't seem to auto-focus. It is supposed to be less than impressive auto-focusing, anyway. I'll revisit this, but it is worth a mention.
  • One other thing? I think so.
I was looking for a replacement, but enjoy these new features:
  • Video. It isn't great, but (like smart-phone video) nice to have in a crunch!
  • Higher ISO. I used to hate shooting over 400, but this isn't bad up to 1600 and the higher modes are way better than unusable pictures, even if they aren't ideal. I was able to get no-flash shots of my dad and brother gigging which were, at least, fun for later review that I never would have been able to get with my D70.
  • Distortion Control -- I've read that it works well, but haven't verified.
  • ADR (Automatic Dynamic Range?) -- also reportedly good, but I'll write if I disagree.
*I didn't know about these differences when I purchased, though they were clearly documented had I looked a little harder.

Good Change

I'm thinking of getting a new old D90 or another, higher end, replacement for my second failed camera that will address my complaints above. I only need two cameras for the rare occasion when my wife and I shoot simultaneously, so won't miss the features at that point. My only complaint, then, will be juggling two types of batteries. I think both will use SD cards for storage rather than the old CF cards my D70 bodies used.

Better Reviews

Friday, July 18, 2014

Ancient A22p LCD has Almost Twice the Pixel Count Compared to most Modern Entry-Level Laptops / Notebooks

Wow -- IBM was doing it right back in the day!

I was taking a brief peak at an ancient IBM Thinkpad A22p before stripping it for parts (doubt i'll be able to salvage much, sadly) and disposing of it when I noticed how crisp the display was, albeit a little dim. Upon closer inspection, this thing has a 1600x1200 (UXGA) -- the same as the 21" Samsung SyncMaster 213T I'm writing this on. That gives it approximately a 133 ppi rating. Not bad. It puts the 95 ppi of my Samsung to shame. Similarly, new (flagship) tablets and smartphones often have higher resolutions than the same group of notebooks/laptops. Sure, I've (finally) seen some 4k monitors and notebooks arriving, but they are usually targeting the professional and their cost usually puts them out of range for normal folks. Anyway, how did we go from 1200 lines of vertical resolutions on laptops (it was targeting cad / business users) to the terrible 768? I guess we can attribute some of it to the change in prominence of the 16:9 aspect ratio, as opposed to older 4:3 or 5:4. I'm not sure why I'm surprised. It is cheaper to provide a horrible, low resolution, monitor. And people don't complain (to be fair: don't notice, sometimes) enough to make a difference.

In summary

Respect to the A22p. I'm sorry I have to put you down.


I'm trying ubuntu/lubuntu and puppy on it.