What is the difference btwn HDMI pass-thru vs. switching vs. upconvert vs. upscale?

[burger]

Help! I'm in over my head looking for a new receiver!

One of the (many) things confusing me is the myriad of HDMI options.

What is the difference between HDMI pass-thru and switching?

What is the difference between HDMI upconvert and upscale?

Why would I need these features?

FWIW, I have a 32" LCD HDTV... not sure if it is 720p or 1080p. I do not currently have any HDMI devices, but do see myself purchasing a new DVD player in the future which would likely be HDMI.

I also want to be sure that if I have an HDMI DVD player that audio can be played thru both the AVR and the TV. I have also read that some AVR's don't pass video thru HDMI. Is that something I need to be worried about? I haven't found anything on manufacturers websites stating exactly what passes thru the HDMI.

Anyway, I'm in over my head. Help!


Ed

 

[jostenmeat]

Help! I'm in over my head looking for a new receiver!

Obviously!

One of the (many) things confusing me is the myriad of HDMI options.

What is the difference between HDMI pass-thru and switching?

They are different things. "pass-thru" is the really confusing one. I'm not even sure there is even a true definition. However, what you will need to know is if it passes VIDEO-ONLY, or if it can handle audio as well. All HDMI receivers will accept video, and switch sources. IOW, don't worry about switching. Just see what it can do with the audio portion,

What is the difference between HDMI upconvert and upscale?

This one is a kicker. I swear they choose utterly ambiguous nomenclature like "upconvert" on purpose simply to confuse poor souls like you and me.

Upconvert on a DVD player basically will change the resolution from the 480i DVD to something that you select in order to match the native rez of your display. Now, even if you did NOT upconvert, your TV automatically will with its own video processing. Its simply a question of which does it better.

Now, say you go to 720p or 1080p as selected upconversion rez from the DVD player. There's a two part process: deinterlacing (to become progressize, or "p"), and upscaling. The first is trickier because fields of video in separate points in time come together as one.

Where people get screwed in misunderstanding is when a receiver also boasts "upconverting", when it actually does nothing for video. Often called "conversion", or better is "transcoding", its when something like component input into the receiver can be output as HDMI. Some only can do this w/ component, some can't do it all, some can do it with many types such as s-video or something.

So, don't get those two types of upconversion confused. DVD is straightforward, its w/ receivers you have to be careful. Now, receivers that can upconvert in the DVD sense obviously can "convert/transcode" component connection.

Why would I need these features?

Why does anyone need anything?

FWIW, I have a 32" LCD HDTV... not sure if it is 720p or 1080p. I do not currently have any HDMI devices, but do see myself purchasing a new DVD player in the future which would likely be HDMI.

Id get a bluray player instead. If not, find a cheap $20 progressive player from a brand name, during the meanwhile.

I also want to be sure that if I have an HDMI DVD player that audio can be played thru both the AVR and the TV. I have also read that some AVR's don't pass video thru HDMI. Is that something I need to be worried about? I haven't found anything on manufacturers websites stating exactly what passes thru the HDMI.

Anyway, I'm in over my head. Help!


Ed

If you get a bluray, stick with Panasonic. Players like Sony require stoopid toggling thru the audio menu (takes time and hassle) if you want to switch between TV and AVR, and that includes the PS3.

I have never, ever heard of HDMI not passing video in a receiver. That would be utterly retarded.

hope this helps.

 

[markw]

Dunno about HDMI switching vs HDMI passthrough but I've always seen "upconversion" and "upscaling " in hte following manner.

"Upconversion" will take a signal from one format to another. i'e, youi could send in a composite (yellow RCA plug) video signal and have it come out over a "higher quality" type of media, say component or HDMI. This really doesn't improve the quality of the picture but it allows one feed from the receiver to the TV. It's more of aconvenience.

"Upscaling", however, appears to be where you take a lower resolution signal and kerfutz with it so it comes out a higher resolution signal. i.e, a 480 signal in can come out a 1080p signal over HDMI. Remember, it can't put in what wasn't there to begin with. There's a lot of math going on for it to "guess" what data should be manufactured and inserted into the picture

How well this works depends on the hardware but it's really not mandatory. All digital TV's have built-in upscalers that will "upscale" whatever signal is input to it's native resolution.

 

[Jack Hammer]

Think of upconversion as related to the cables used. It's where your AVR takes in one type of input, like a component video signal, and outputs it as a higher quality connection output, like HDMI. This allows you to connect several different types of cables to your AVR and use only one cable out to your TV.

Video upscaling is where the resolution of the video is increased. A DVD is recorded at 480 lines of resulotion and played out to your TV at up to 1080 lines of resolution.

HDMI passthru is where your reciever lets an HDMI signal 'pass thru' it without doing any additional conversion, processing, or enhancement to the signal.

HDMI switching means you can have multiple HDMI cables connected to your AVR and it will automatically change which one to output to your TV based on which source you select.

Jack

 

[MichaelJHuman]

HDMI Passthrough is used by some manufacturer's as an odd way to indicate they don't handle HDMI audio.

Some people use the term to mean they don't want any processing. Make sure you know what usage is intended.

 

[TLS Guy]

HDMI Passthrough is used by some manufacturer's as an odd way to indicate they don't handle HDMI audio.

Some people use the term to mean they don't want any processing. Make sure you know what usage is intended.

There is more to it than that. HDMI is two way street. A display needs only to make one hand shake. Much of the gear coming out now, including things like Direct TV HD DVRs, require repeated handshakes from anything that is not a display. A pass through device will not do that. I have proved that a Direct TV HD DVR, current models anyway, will not pass a signal through any type of switch that does not have repeater architecture. Because of the regs there will be more and more products like that coming on stream.

If you don't want obsolescence, then I would think twice about buying a pass through unit.

 

[burger]

If you don't want obsolescence, then I would think twice about buying a pass through unit.

Thanks for the reply.

It was for this very reason that I decided to purchase a Yamaha RX-V663 instead of the Onkyo 505/506 AVR's that I initially looked at. The two Onkyo units are lacking in HDMI, as they are pass-thru only. The Yammy is a repeater and will upconvert 480i to 480p. I'm hoping that this will improve the quality coming from my DVD player. I am also curious if this will help older sources, such as our VCR.