Gospelization

The movement of notes, drafts, info …

Video Streaming Test

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* Latest update was on 9 July 2008, so this tech research may be quite old. Nevertheless, I just post here for my reference.. And oh yes, the video files are probably linked here will probably disappear sooner or later; nevertheless, what’s important are the information..
Taking ipod nano device as a test, it seemed that a bitrate of 384kbps at screen size 320×240 is sufficient for viewing whiteboard scribblings.

Adobe Flash can be played 100% on all websites, H.264 is best on portable players and if quality is very importan. WMV has a little bit lower quality but eats less resources. This page is done to do up H.264, with best quality in smallest size, embedding it in MP4 container, and embedding in Adobe flash for web distribution. I believe H.264 is the best compression/distribution (supporting low bandwidth and HDTV) to date. The embedded media player is done by script called (jw flv player that uses Adobe flash). The mp4 must be arranged in a way so that the header information must be at the front to allow for pseudo-streaming. Please use Adobe Flash version 9 (upgrade if needed) for full H.264 compatibility.

Welcome to give comments, or more even tests of your own to find out the recommended bitrate audio and video quality for especially making out whiteboard characters and emphasis on quality on audio message.

Aim: to find the best codec, and profile for personal portable mp4 players and for web-streaming.

1. Comparisons
1) Sample which works with pseudo-streaming
KMTV Flash H264 Test.html
2) Full WDC Video, Ezra Part 3, works with pseudo-streaming, but resized to 320×240 ipod video size (H.264AVC 25fps video, AAC/44kHz/mono audio, total 705Kbps)
h264test.html, using http://www.lifechurchmissions.com/downloads/WG/VideoTest/Tue20060829_Ezra_3_WG.super.MP4 at 167MB in size (1.52 MB/min video)
The original video at http://www.spring4life.net/downloads/Video/Tuesday/Tue20060829_Ezra_3.wmv is 442MB in size (4.03 MB/min video)
Pastor Choo tested on ipod nano and the notes written by Rev Leechull on whiteboard were discernable.
3) DVD 720×480 resolution video from

2. Video Conversion from MPG or any format for ipod/web
1) Use eRightSoft SUPER converter (converts “all” video/audio formats except WMV9/VC-1)
local download – http://www.lifechurchmissions.com/downloads/WG/VideoTest/SUPERsetup.exe

3. JW FLV Media Player
1) An easy and flexible way to add video and audio to websites using the Adobe Flash Player (which presently can now handle formats [FLV, but also MP3, H264, SWF, JPG, PNG and GIF].
http://www.jeroenwijering.com/?item=JW_FLV_Player
2) Wizard to render the embedded code needed inside the html
http://www.jeroenwijering.com/?page=wizard
3) or just right-click, save the html examples in Point 1 above on comparisons.

4. Pseudo-Streaming / Progressive Download
(Video starts even when the download for the whole video is not yet completed)
Taken from http://www.jeroenwijering.com/?thread=7522 :

For some reason when the .mp4 is encoded with certain software moov atom data is put at the end of the file instead of the beginning so once it has completely loaded the .mp4 file begins to play. The fix is run a simple DOS script that puts the moov atom data in the beginning. One way is to use the freeware MP4Box
http://www.videohelp.com/tools/mp4box
It’s DOS based so simply put the files in the same folder and run the follwing command:
mp4box -inter 300 example.mp4
300 represents 3 seconds, i believe and we found it to load the video nicely with a decent buffer.
Also the a complete instructions for it can be found here:
http://gpac.sourceforge.net/doc_mp4box.php#general

1) For Machintosh *.mov files, search for “QTFastStart” script (downloadable here: http://www.lifechurchmissions.com/downloads/WG/VideoTest/QTFastStart.zip), which places header of MP4 generated by “Super converter” at the front
2) For PCs, use mp4box as the instructions above stated:
C:\Vtest> mp4box -inter 300 example.mp4

5. Resources for tests:
1) Test Directory – http://www.lifechurchmissions.com/downloads/WG/VideoTest/
2) 40 seconds of sample video in raw/original format (AC3Filter audio, GPL-MPEG-1/2Decoder video) cut out for testing – 34.1 MB
http://www.lifechurchmissions.com/downloads/WG/VideoTest/TueSample.raw.mpg
3) wmv format (as used at http://www.spring4life.net) of the above 40s video (wma9.1/128kbps/44kHz/stereo-1-passCBR audio, wmv9pro/427Kbps/720×480/29.97fps video)
4) mp4 format (H.264AVC/29.97fps/720×480 video, AAC/44kHz/stereo/128kbps audio) of the above 40s video

6. Definitions
1) pseudo-streaming
The audio or video files are placed on a standard web server and linked to with fairly standard methods. When the user goes to play the media, the web browser or playback application does not need to download the whole media file before playback begins. Instead, it downloads just enough to create a buffer (think of “headroom”) and begins playback. This method works out well for shorter audio and video files, and simplifies technology needs greatly.
2) Genuine streaming
There is one big drawback to pseudo-streaming: Because the file is being downloaded and played back in real time, the user cannot skip ahead to a point, say, 14 minutes into the presentation. To allow this, an actual streaming media server must be set up alongside the normal http/web server.
3) MPEG-1
Video compression used by VCD
4) MPEG-2
Video compression used by SVCD, DVDs, etc..
5) MPEG-4
Video compression used by Blu-ray, yet also possible for low-bitrates for web distribution
6) H.264
The next-generation video compression technology in the MPEG-4 standard, also known as MPEG-4 Part 10. H.264 can match the best possible MPEG-2 quality at up to half the data rate. H.264 also delivers excellent video quality across the entire bandwidth spectrum — from 3G to HD and everything in between (from 40 Kbps to upwards of 10 Mbps). Also known as MPEG-4 Part 10, or MPEG-4 AVC (for Advanced Video Coding), 1st draft finalized in May 2003 by the ITU-T Video Coding Experts Group (VCEG) together with the ISO/IEC Moving Picture Experts Group (MPEG) as the product of a partnership effort known as the Joint Video Team (JVT).

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