Friday, June 12, 2009

How to know the quality of the video?

I know things, but i need to know all the little things that affect the quality.
this stuff...
Format profile : Advanced Simple@L5
Format settings, BVOP : 2
Format settings, QPel : No
Format settings, GMC : No warppoints
Format settings, Matrix : Default (MPEG)
Muxing mode : Packed bitstream
Codec ID : XVID
Codec ID/Hint : XviD
Duration : 1h 43mn
Bit rate : 1 762 Kbps
Width : 640 pixels
Height : 272 pixels
Display aspect ratio : 2.35:1
Frame rate : 23.976 fps
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Compression mode : Lossy
Bits/(Pixel*Frame) : 0.422
Stream size : 1.27 GiB (93%)
Writing library : XviD 61

Answer on How to know the quality of the video?

The main specs that affect the video quality are:

- The Resolution (measure of the height & width of the video in pixels - the maximum amount of detail recorded in each frame)
- The Bit-Rate (the amount of image detail that is recorded per second of video)
- The Codec (different codecs use different algorithms to compress and format video and the resulting quality will vary depending on which codec is used. Generally speaking, the preferred codec is H.264, used for online video and even Blu-Rays.

Also how long is the video? Considering the bit-rate, the file-size seems pretty big. Also judging by the aspect ratio of 2.35:1, I'm guessing this is a commercial film? In which case this has nothing to do with Youtube and I'm not sure why you're asking this question here.

Anyway, for optimal settings:
- Use a Resolution of 480p (640 wide x 480 tall), 720p (1280x720) or 1080p (1920x1080). Your current resolution of 640x272 will result in low-resolution video with limited detail. The file-size will be proportional to the resolution you select.

Since your video/movie is in 2.35:1 aspect ratio, the actual resolution can be formatted to be 1280x544 or 1920x817 to avoid recording useless detail of the black-bars above and below the video.

- The bit-rate should exceed 5 Mbps (~5,000 kbps) in order to produce high quality video. Ideally the bit-rate should be higher than 10 Mbps, especially for HD content. Blu-Ray movies by comparison may have bit-rates of 40 Mbps. The file-size is directly proportional to the bit-rate chosen.

- The codec is also important. Generally speaking, H.264 is the industry standard for encoding video on various different platforms. It provides the 'best bang for the buck' (in other words, the highest quality with the lowest bit-rate and the fastest processing times on accelerated hardware) compared to other competing codecs. DivX is also a popular codec, but I personally do not use it. VP8/WebM (by Google) is a relatively new codec that is both free and roughly equivalent to H.264 in terms of quality and performance, but most software and hardware devices are not equipped to playback WebM video.

Weight loss in my 10 month old?

I have a very active 10 and a half month old girl who weighs 21 pounds. I am concerned as she hasn't been putting on any weight, she has actually been loosing weight. At her 9 month appointment she was 20 pounds (9.1kg) than she went up to 22 pound (10.kg). She is now down to 21 pounds (9.3kg). So she is loosing weight, although overall it works out to .2kg since her appointment almost 2 months ago.

She drinks on a good day 20oz of milk and three meals. Although she doesn't eat her meals well. Especially breakfast. She barely eats.

She is crawling like crazy since she's 9 months, and she is also teething. She has cut 6 teeth, and is cutting more at the moment (I think).

Just wondering when weight loss in a baby should be a concern. SHe seems happy overall.

Thanks.

Answer on Weight loss in my 10 month old?

I wouldnt worry about the weight unless it is a drastic change. once babies start to move around alot and get more active they tend to either not gain any weight or lose a pound or two.