Running and Passing.

Archive for January, 2010

Low Clock Speed Decoding : H.264 Decoders & Processor Speed

I recently did some investigating into h.264 decoding options for a aged Toshiba laptop that I have been using as my media center. The system in question is running Windows XP and sports an Intel mobile Celeron 2.2 Ghz processor (400mhz fsb + 256kb cache), 1GB Ram, Intel i852GM chipset, 82852/82855 GM/GME graphics adapter, and 4200 rpm hard drive. Hardly specs one would associate with any a modern media center.

The video card does not support hardware decoding of HD content, so I am forced to rely solely on processor power. However, I only outputting video to the laptops 15″ screen. My media center pc only needs to be able to handle my music collection, stream online media, and play a variety of offline video including, fairly low bitrate 720p h.264.

VLC is my media player of choice, but I was running into some problems playing 720p video. For h.264 playback, VLC utilizes the open source FFmpeg codec and does not support third party/system codecs. This is a blessing and a curse. VLC is well known for playing practically any media one can throw at it, but that comes at the price of not always offering the most efficient decoding options. This is not a problem in most cases, but I needed something highly efficient if my Celeron was going to have a chance at playing HD content.

In it’s default state VLC was unable to render watchable video. Processor usage was pegged at 100% and high bitrate scenes were suffering from constant frame drops. However, by utilizing the following tweaks, I was able to attain very watchable, good quality playback.
VLC-Preferences-Codecs-FFmpeg-decoder
* Open the preferences
* Tick advanced in the lower right corner
* Go to “Input/Codec”
* Go to “other codecs” subcategory
* Go to “FFmpeg”
* Change “Low Resolution Decoding” to 1 or 2
* Tick “Allow Speed Tricks”
* Change “skip the loop filter for H.264 decoding” to all. <– aka Deblocking
* Restart VLC

Depending on system specs, one may not have to implement all of the tweaks. A good course of action would be to  enable one at a time, then try combinations until a efficient decoding process emerges.

Another alternative is to use a different decoder. The CoreAVC codec and Divx 7 are two third party h.264 decoders said to offer superior performance compared to FFmpeg. However, both codecs are proprietary software. Divx 7 is available as a free decoder download, while CoreAVC is available for $10.

To enable these decoders,  an different media player must be. My reliable fallback is the the aptly named Media Player Classic (MPC). In this case, I used Media Player Classic – Home Cinema. MPC is lightweight, open source, and most importantly, supports external filters/decoders.

After installing a 3rd party decoder, navigate to it’s start menu folder and you will be able to configure playback options, interlace methods, and deblocking preferences. Use the following steps to add decoding codecs to MPC.

* Click “View” -> “Options” -> “External Filters”
* Select “Add Filter” from the right menu and select your decoder
* You can then choose to ‘prefer’ or ‘block’  usage so as to ensure you are running the decoder of choice.
Media-Player-Classic-Options-External-Filters
Between CoreAVC and Divx 7, CoreAVC was the clear winner. It succeded in blowing away both Divx 7 and FFmpeg.  Processor usage with CoreAVC was 20%+/- lower AND I was able to leave deblocking turned on, something I was unable to do while running either of the other decoders.

VLC, MPC, and the decoders are fully supported by all recent flavors of Windows (XP, Vista, or 7). Decoding speeds will vary according to cpu type, chipset, and ram and decoding codecs should be tested to ensure optimal performance. For example, at the time of this post (01/24/2010), the VLC FFmpeg codec does not support multi-core processing. Also, while real world testing does hold the trump card, GraphStudio provides an excellent base for benchmarking decoders.

Since I have both VLC and MPC installed on the system, I will continue to run both programs as needed. I still like VLC a bit more, but MPCs ability to utilize the CoreAVC decoder and thus provide slightly higher quality playback makes it a must for my lowly mobile Celeron. H.264 Bitrates higher than 3600-3800 kb/s still choke the system, but I am no longer limited to non HD content. Even on more high end systems, these tweaks and decoders can aid in playback and provide some options as to performance preferences.

Great resources for digital video conversation include : forum.videolan.orgforum.doom9.orgforum.videohelp.com

Written by Matt Kowal

January 24th, 2010 at 1:25 am

Olafur Eliasson’s Round Rainbow @ The Hirschorn Museum, 2007

In November of 2007, I viewed Olafur Eliasson‘s Round Rainbow at Washington, D.C.’s Hirschorn Museum. It made an immediate impression upon me. I stood silent for roughly 20 min just watching this simple creation spin light and pattern around the darkened space. Consisting solely of acrylic glass, a HMI spotlight, motor, and tripod, the work seemed to be much more than the sum of its parts. I remember smiling as color and light wrapped around the room, seemingly drawing all mass and energy toward the rotating acrylic ring. Simple, silent and oh so heady.

View the entire Round Rainbow set on my Flickr account.

Olafur Eliasson, Round Rainbow, 2005 @ The Hirschorn Museum, Washington D.C. 2007. Photo by Matt Kowal

Olafur Eliasson, Round Rainbow, 2005 @ The Hirschorn Museum, Washington D.C. 2007. Photo by Matt Kowal

Olafur Eliasson, Round Rainbow, 2005 @ The Hirschorn Museum, Washington D.C. 2007. Photo by Matt Kowal

Written by Matt Kowal

January 20th, 2010 at 10:04 pm

Creative Commons License : REMIXed for sharing and commerce.

I recently read the Lawrence Lessig book Remix: Making Art and Commerce Thrive in the Hybrid Economy and have been toiling with the idea of licensing some of my work under either a Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License or a Creative Commons Attribution-Noncommercial 3.0 United States License.

My reasons for licensing would be  fourfold, 1) inspire others to create work and modify my ideas 2)  make people more away of my work, by allowing it to be easily distributed, remixed, etc 3) create a community, collaboration, etc, between myself and others 4) foster a greater awareness for the Creative Commons.

I developed my passion for creating photography and art through appropriation. My primary introduction to photography was through PC based digital imaging. However, I had no camera or digital camera, so I began my creating my own digital work the incorporating appropriation and collage .  I was concerned about copyright and my ability to create unique work. Thus, my early efforts were very layered. This method of learning no doubt grew my desire to create work with a more personal foundation. However, even when creating unique imagery, I would be fooling myself to think that outside influences are not present. To this day, I still occasionally utilize appropriation when creating work.

I owe some part of my education to the fact that I was able to copy, disassemble and manipulate work to which I held no copyright. My early work was quite amateurish and at no point was I competing with professional outlets or hindering artistic economics. I recognize that the ability to non-commercially appropriate work helps to greatly expand distribution. It can also inspire, educate and give voice to a new generation of creative thinkers, tinkers, and the media minded. So long as individuals are compensated for professional work, those producing amateur derivative works are likely committing no wrong.

I’d love for people to taking something away from my work, be it educational, aesthetics, or a simple story. The complexity of copyright and the current state of cultural sharing/stealing is something that I find confusing. Every time I open a file on my computer a virtual copy is made. I see no immediate reason not to use the CC to license the work, but am concerned when dealing with the future licensing issues and the perceived lack of control I would have over any work.

Would I not be in a better situation if I simply reserved all right, then enforced my right to copyright on a case by case basis? I would be more than willing to work with parties interesting in licensing works under alternative terms, some of which would include CC, but those seem to be best dealt with on an individual basis.

No one may doubt the strict authorship of a piece of audio/video/imagery, but who should decide when, where, or under what conditions it is appropriate to use this media? It is certainly true that once media is digitized it is immensely more hard to control it’s distribution and usage.

I’m learning more and more about utilizing a Creative Commons license and am hoping to receive some community feedback. For now, I am simply questioning the appropriateness of licensing the work and seeking examples of individuals who have successfully used Creative Commons to licensed work and maintained a professional/fine art/commercial standing.

I have started by licensing my Flickr imagery, an audio artwork, and this post.

Any opinions, comments, or suggested reading would be most appreciated.

Creative Commons License
This post by Matthew Kowal is licensed under a Creative Commons Attribution 3.0 United States License.

Written by Matt Kowal

January 9th, 2010 at 1:48 pm