How is it possible to watch TV on your phone?

[ShawnD]

I'm not quite understanding this, so I'll lay down some assumptions and describe how this is puzzling.

Assumptions

1. cellular phones use digital signal.
This is true of most areas. The switch was from analog to digital because digital gives much longer battery life (days compared to a couple hours).

2. DSL and cable internet are digital.
Because internet is digital...

3. DSL and cable have more bandwidth than cell phones.
Anybody who has used their phone for their internet can support this one. Cell phones give good signal but they're crap compared to DSL and cable.

4. DSL and cable do not have enough bandwidth to play steady streaming videos.
Have you noticed that when you try to play a video on the internet, you need to download (buffer) a lot of the video before you can start to play it since the playback rate is higher than your download rate? I can download at 160KB/s (that's bytes, not bits) and that's not nearly enough to play streaming video.


problem

If I can't play streaming video over my DSL connection, which has more bandwidth than a cell phone, how is it possible to watch TV on a phone?

 

[Pengwuino]

I'll toss in some suggestions here:

1) High compressions
2) Low resolution (it is a small screen on a cell phone...)

I personally can stream videos far in excess of 160KB/s... I think I've done a 300KB/s stream before on comcast cable.

 

[Jelfish]

Also, it might not be necessary, if current technology is insufficient, to actually stream live. Due to the popularity of pod-casting, a lot of people would probably be interested in downloading recent programs and watching them later.

 

[Cyrus]

Because we have pitiful internet connection speeds as say, Japan or Korea, which make our internet look like a JOKE.

 

[tribdog]

the phone video is also only 20 frames per second, 4 fps slower than full-motion video
and the networks are supposed to be up to 2.4 Megabits per second which is almost as fast as a cable modem.

 

[Pengwuino]

NTSC is 30FPS.

 

[ShawnD]

I personally can stream videos far in excess of 160KB/s... I think I've done a 300KB/s stream before on comcast cable.

When it says 300kb it actually means bits, so that's only 37.5KB/s, and that video quality is usually just horrible. High video compression seems unlikely since higher compression needs more processing power. A cell phone doesn't have enough power to play something with very high compression, like an AVI video.

 

[Pengwuino]

When it says 300kb it actually means bits, so that's only 37.5KB/s, and that video quality is usually just horrible. High video compression seems unlikely since higher compression needs more processing power. A cell phone doesn't have enough power to play something with very high compression, like an AVI video.

... i stream 300 kilobytes/second. I don't know how bad your connection is lol. Or well, that 300KB/sec wasn't exactly a normal video to say the least lol

 

[ShawnD]

the phone video is also only 20 frames per second, 4 fps slower than full-motion video
and the networks are supposed to be up to 2.4 Megabits per second which is almost as fast as a cable modem.

Alright then. This sounds more than reasonable for streaming video. Thanks trib.

 

[tribdog]

thank Popular Science magazine they have a little article I quoted almost word for word.

 

[russ_watters]

4. DSL and cable do not have enough bandwidth to play steady streaming videos.

Have you noticed that when you try to play a video on the internet, you need to download (buffer) a lot of the video before you can start to play it since the playback rate is higher than your download rate? I can download at 160KB/s (that's bytes, not bits) and that's not nearly enough to play streaming video.

I don't know what streaming videos you are trying to watch, but my Comcast cable is 4 megabits, standard dvd is 1.2 megabits, and well-compressed, tv quality RealPlayer, divX, wmv media only really needs to be about .3 megabits.

I've watched plenty of streaming video with no problems.

Perhaps you have a connection problem?

When it says 300kb it actually means bits, so that's only 37.5KB/s, and that video quality is usually just horrible.

That's 1/4 DVD's bitrate for slightly lower quality video, while using a far superior compression algorithm. That isn't that difficult to do. And if the cell phone is 320x200 (near tv quality), that's about 1/5 the data requred even for dvd (Mpeg2) video (without better compression).

High video compression seems unlikely since higher compression needs more processing power. A cell phone doesn't have enough power to play something with very high compression, like an AVI video.

You'd be surprised at the processing power you're looking at - a cell phone designed for video can match a handheld's power (heck, some are CE based pc's). Besides - the key is hardware decoding: a special chip that only decodes one type of video. That's how it used to be possible to watch dvd on a 200mhz Pentium pc.

 

[Kakarot]

some new phones in japan are said to have speeds in gb/s but i doubt we will see them any time soon. i stream movies at 1000k/sec sometimes and its really good quality

 

[mattmns]

The question I must ask is: Who in the hell would want to watch TV on a screen that small?

 

[Cyrus]

What do you mean small, you could have one side of the phone just a screen, and the other side a smaller screen for calling and buttons.

 

[mattmns]

What do you mean small, you could have one side of the phone just a screen, and the other side a smaller screen for calling and buttons.

Well I have never seen such a phone.

 

[Evo]

There is a "tv" option you buy with your cellular service. The regular option for non EVDO (high speed wireless broadband on your cellular phone) are tv "clips". There is another option for streaming tv on your cell phone now.

http://www1.sprintpcs.com/explore/ueContent.jsp?scTopic=multimedia192