Thanks to my recent experiments with code coverage tools, I have a powerful new — admittedly somewhat specious — method of comparing programs. For example, I am certain that I have read on more than one occasion that Apple’s H.264 encoder sucks compared to x264 due, at least in part, to the Apple encoder’s alleged inability to exercise all of H.264’s features. I wonder how to test that claim?

Experiment
Use code coverage tools to determine which H.264 encoder uses the most features.

Assumptions

• Movie trailers hosted by Apple will all be encoded with the same settings using Apple’s encoder.
• Similarly, Yahoo’s movie trailers will be encoded with consistent settings using an unknown encoder.
• Encoding a video using FFmpeg’s libx264-slow setting will necessarily throw a bunch of H.264’s features into the mix (I really don’t think this assumption holds much water, but I also don’t know what “standard” x264 settings are).

Methodology

• Grab a random Apple-hosted 1080p movie trailer and random Yahoo-hosted 1080p movie trailer from Dave’s Trailer Page.
• Use libx264/FFmpeg with the ‘slow’ preset to encode Big Buck Bunny 1080p from raw PNG files.
• Build FFmpeg with code coverage enabled.
• Decode each file to raw YUV, ignore audio decoding, generate code coverage statistics using gcovr, reset stats after each run by deleting *.gcda files.

Results

• x264 1080p video: 9968 / 134203 lines
• Apple 1080p trailer: 9968 / 134203 lines
• Yahoo 1080p trailer: 9914 / 134203 lines

I also ran this old x264-encoded file (ImperishableNightStage6Low.mp4) through the same test. It demonstrated the most code coverage with 10671 / 134203 lines.

Conclusions
Conclusions? Ha! Go ahead and jump all over this test. I’m already fairly confident that it’s impossible (or maybe just very difficult) to build a single H.264-encoded video that exercises every feature that FFmpeg’s decoder supports. For example, is it possible for a file to use both CABAC and CAVLC entropy methods? If it’s possible, does any current encoder do that?

Here’s a document I scavenged from my archives. It was dated September 1, 2001 and I now publish it 9 years later. It serves as sort of a time capsule for the state of media player programs at the time. Looking back on this list, I can’t understand why I couldn’t find MPlayer while I was conducting this survey, especially since MPlayer is the project I eventually started to work for a few months after writing this piece.

For a little context, I had been studying multimedia concepts and tech for a year and was itching to get my hands dirty with practical multimedia coding. But I wanted to tackle what I perceived as unsolved problems– like playback of proprietary codecs. I didn’t want to have to build a new media playback framework just to start working on my problems. So I surveyed the players available to see which ones I could plug into and use as a testbed for implementing new decoders.

Regarding Real Player, I wrote: “We’re trying to move away from the proprietary, closed-source ‘solutions'”. Heh. Was I really an insufferable open source idealist back in the day?

Anyway, here’s the text with some Where are they now? commentary [in brackets]:

Towards an All-Inclusive Media Playing Solution for Linux

I don’t feel that the media playing solutions for Linux set their sights high enough, even though they do tend to be quite ambitious. Continue reading →

My new EeePC 1201PN netbook has 2 GB of RAM. Call me shortsighted but I feel like “that ought to be enough for me”. I’m not trying to claim that it ought to be enough for everyone. I am, however, questioning the utility of swap space for those skilled in the art of computing.

Technology marches on: This ancient 128 MB RAM module is larger than my digital camera’s battery charger… and I just realized that comparison doesn’t make any sense

Does anyone else have this issue? It has gotten to the point where I deliberately disable swap partitions on Linux desktops I’m using ('swapoff -a'), and try not to allocate a swap partition during install time. I’m encountering Linux installers that seem to be making it tougher to do this, essentially pleading with you to create a swap partition– “Seriously, you might need 8 total gigabytes of virtual memory one day.” I’m of the opinion that if 2 GB of physical memory isn’t enough for my normal operation, I might need to re-examine my processes.

In the course of my normal computer usage (which is definitely not normal by the standard of a normal computer user), swap space is just another way for the software to screw things up behind the scenes. In this case, the mistake is performance-related as the software makes poor decisions about what needs to be kept in RAM.

And then there are the netbook-oriented Linux distributions that insisted upon setting aside as swap 1/2 gigabyte of the already constrained 4 gigabytes of my Eee PC 701’s on-board flash memory, never offering the choice to opt out of swap space during installation. Earmarking flash memory for swap space is generally regarded as exceptionally poor form. To be fair, I don’t know that SSD has been all that prevalent in netbooks since the very earliest units in the netbook epoch.

Am I alone in this? Does anyone else prefer to keep all of their memory physical in this day and age?

Fair warning: I’m just going to use this post to blather disconnectedly about a new-ish toy.

I really like my new EeePC. I was rather enamored with the original EeePC 701 from late 2007, a little box with a tiny 7″ screen that is credited with kicking off the netbook revolution. Since then, Asus has created about a hundred new EeePC models.

Since I’m spending so much time on a train these days, I finally took the plunge to get a better netbook. I decided to stay loyal to Asus and their Eee lineage and got the highest end EeePC they presently offer (which was still under US$500)– the EeePC 1201PN. The ’12’ in the model number represents a 12″ screen size and the rest of the specs are commensurately as large. Indeed, it sort of blurs the line between netbook and full-blown laptop.

Incidentally, after I placed the order for the 1201PN nearly 2 months ago, and I mean the very literal next moment, this Engadget headline came across announcing the EeePC 1215N. My new high-end (such as it is) computer purchase was immediately obsoleted; I thought that only happened in parody. (As of this writing, the 1215N still doesn’t appear to be shipping, though.)

It’s a sore point among Linux aficionados that Linux was used to help kickstart the netbook trend but that now it’s pretty much impossible to find Linux pre-installed on a netbook. Continue reading →