Category Archives: 3. Multimedia

Cameras and printers

Today we learned about cameras.

We learned that different types of will have different frame rates. Cheap £20 phones will have very poor video quality. HD video on a phone is better, a digital camera is better than that, a professional camera will be better and a proper TV camera will produce the best quality.

Some cameras have a digital delay.

We also learned that AVI stands for Audi Video Interface. AVI is a windows base format which interleaves video sound and video data.

QuickTime – CODEC was developed by apple but can be used by both Mac and PC. It, like AVI, interleaves sound and video data.

We learned that accurate depends on compression technique, frame rate and resolution.

Speed – Hardware must be fast enough to cope with stream of to memory and to the hard disk.

A digital TV tunes can turn a computer into a digital TV. Good for people who want a computer and TV.

Film replaced by an array of photosensitive cells. Images stored electronically using photosensitive diodes called shared coupled devices (CCDs). The intensity of light is recorded in an image.

Analogue values converted to digital using ADC. Compression usually takes place. Bitmap files are turned into JPEG.

Accuracy is measured in pixels and mega pixels. More is better and less is worse. The accuracy depends on the array of photosensitive cells. The more sensors the smaller they are the higher the resolution.

But depth is in proportion to the number of colours that can be represented. Bit depth is very important on cameras.

Ink is very advanced and difficult to make. That is why it is to expensive.

Inside the pint of a cartage there is a chamber. It is heated and the liquid expands into a bubble. This bubble slowly pops and that is how ink is printed.