Football Broadcasts All Fuzzy For The 'far' Shots?

[pgdownload]

Broadcasting changes in the sports area is moving rapidly but I have long wondered about the following poor PQ 'anomaly' that only affects far shots (ie taken from the stands). Basically shots showing a lot of the field tend to have really pronounced 'blockiness' around players - that is the grass looks like its been run through the lowest JPEG conversion algorythm possible - this creates an almost halo effect (of poor PQ) around players (esp when moving).

Would just put it down to poor broadcast standards but any sort of close up shot (ie taken from the boundary) is absolutely crystal clear (grass or no grass in the immeadiate background). Are they simply using different equipment around the stadium?

Just to clarify:

1) Only refering to SD channels (don't know about the HD ones)

2) I'm using a very good 32" HD CRT so its not due to the screen technology.

3) Effect only occurs on far shots from the stand (ie see 10+ players at the same time).

4) Close up is always crystal clear.

Be interested in any theories.

Peter Gillespie

[Grampus]

Broadcasting changes in the sports area is moving rapidly but I have long wondered about the following poor PQ 'anomaly' that only affects far shots (ie taken from the stands). Basically shots showing a lot of the field tend to have really pronounced 'blockiness' around players - that is the grass looks like its been run through the lowest JPEG conversion algorythm possible - this creates an almost halo effect (of poor PQ) around players (esp when moving).

Would just put it down to poor broadcast standards but any sort of close up shot (ie taken from the boundary) is absolutely crystal clear (grass or no grass in the immeadiate background). Are they simply using different equipment around the stadium?

Just to clarify:

1) Only refering to SD channels (don't know about the HD ones)

2) I'm using a very good 32" HD CRT so its not due to the screen technology.

3) Effect only occurs on far shots from the stand (ie see 10+ players at the same time).

4) Close up is always crystal clear.

Be interested in any theories.

Peter Gillespie

I wonder how many good quality cameras are available to the broadcaster?

Is the good quality shot you see something that has come in close from a poor quality long range shot? (same camera), or is it a different camera?

[Crowley]

Broadcasting changes in the sports area is moving rapidly but I have long wondered about the following poor PQ 'anomaly' that only affects far shots (ie taken from the stands). Basically shots showing a lot of the field tend to have really pronounced 'blockiness' around players - that is the grass looks like its been run through the lowest JPEG conversion algorythm possible - this creates an almost halo effect (of poor PQ) around players (esp when moving).

Would just put it down to poor broadcast standards but any sort of close up shot (ie taken from the boundary) is absolutely crystal clear (grass or no grass in the immeadiate background). Are they simply using different equipment around the stadium?

Just to clarify:

1) Only refering to SD channels (don't know about the HD ones)

2) I'm using a very good 32" HD CRT so its not due to the screen technology.

3) Effect only occurs on far shots from the stand (ie see 10+ players at the same time).

4) Close up is always crystal clear.

Be interested in any theories.

Peter Gillespie

i would have thought its simply down to the fact that a wide shot would have a far bigger mix of moving content so the encoders simply cant cope, the closer you get the more static things are and the easier the encoding is, that plus the bitrate available.

[gtr73]

Yeah, some of the sports broadcasts on SD DTV look like "podcasts" from the net.

Did anyone see the water polo on Nine's coverage of the World Swimming Championships last week? Absolutely disgraceful!

Anywho, basically some of the cause's of this problem are:-

- Your connections. If possible, HDMI or component connections should be used. SVideo and Composite usually cause soft vertical edges in the picture, for example.

- Digital Bandwidth, probably the main offender IMO, broadcasters must use more bandwidth resource to telecast full digital. A lot of the time they don't or can't, especially for sport, and a "degraded" digital transmission is the result. A lot of reasons for this - HD cameras are generally not used, FTA broadcasters sometimes buy a sports event off Foxtel so there'll be a 10 or 7 van parked next to a Foxtel van and lots of cables in between, then a couple of analogue components thrown in the mix. Result: blocky "podcast" picture.

- Compared to your old, smaller CRT, new large higher resolution screens make any reduction in PQ more obvious.

When analogue is finally switched off, the hope is FTA broadcasters will have there poo in a pile and have all their resources put into digital. The we'll finally get the consistent quality digital broadcast we'd like.

[Kas]

...... poor PQ 'anomaly' that only affects far shots (ie taken from the stands). ....

Hi Peter, just came across this thread and your "anomoly" rang a bell.

I work with digital still images. The level of complexity in an photo (ie number of colour changes as you move through the pixels) affects the "efficiency" of a compression. A simple image with large slabs of colour (a close up) will compress down to a small file size while a complex image (eg a crowd) of the same dimensions, resolution and compression level will have a much larger file size. So with the bit rate or bandwidth of the digital broadcast signal fixed, I would expect the complex images need more compression to stay under the size limit.

[pgdownload]

Hi Peter, just came across this thread and your "anomoly" rang a bell.

I work with digital still images. The level of complexity in an photo (ie number of colour changes as you move through the pixels) affects the "efficiency" of a compression. A simple image with large slabs of colour (a close up) will compress down to a small file size while a complex image (eg a crowd) of the same dimensions, resolution and compression level will have a much larger file size. So with the bit rate or bandwidth of the digital broadcast signal fixed, I would expect the complex images need more compression to stay under the size limit.

Thanks kaz. Am familiar with the concept and suspect you're probably correct. However, I did notice a recent broadcast that might highlight this 'deficiency' - it was the WC cricket celebrations with the champaign being sprayed around. The pixelation and macroblocking just went nuts as something tried to encode all the drops. I pressume on a wide angle field shot the small colour variations (not to mention croud etc.) might be taxing the encoder

Might be a smart idea if the software could somehow be optimised to encode the centre of the screen to a higher level.

Anyway, thanks for the replies. Not sure we've found the root cause but I'm just glad I don't really like watching sport

Regards

Peter Gillespie

[KernelPanic]

Thanks kaz. Am familiar with the concept and suspect you're probably correct. However, I did notice a recent broadcast that might highlight this 'deficiency' - it was the WC cricket celebrations with the champaign being sprayed around. The pixelation and macroblocking just went nuts as something tried to encode all the drops. I pressume on a wide angle field shot the small colour variations (not to mention croud etc.) might be taxing the encoder

Might be a smart idea if the software could somehow be optimised to encode the centre of the screen to a higher level.

Anyway, thanks for the replies. Not sure we've found the root cause but I'm just glad I don't really like watching sport

Regards

Peter Gillespie

MPEG uses a number of methods to achieve its compression.. Among them is a JPEG like compression for Key Frames (they broadcast a full image every x frames.) The remaining frames between the keyframes use a host of techniques, but the full frames arent transmitted. Basically they will predict the frame based on what has changed (movement and blocks) from the previous frames.) More movement, means more changes from previous frames -- more information is discarded to keep to the required stream size. Also, more detail, such as the crowd, means encoding has to work very hard to keep to the same size.

Basically (for afl) the main problem is that the streams do not have enough bit rate.

Problems in overseas broadcasts are often related to the fact that its compressed for overseas distribution, and then recompressed locally for the DTV streams. Re-encoding material always has disasterous results.

[FMB]

It could just be that you were watching a West Coast Eagles game and it was the players themselves that were 'fuzzy'

[Dork(original)]

It could just be that you were watching a West Coast Eagles game and it was the players themselves that were 'fuzzy'

Fmb,gold for that one Dork

[Strada916]

I think they are just using old technology cameras to shoot from the grand stands, ie analoge. As HD digital cameras are expensive, and any logistic that goes with that ie cables, hardware etc, would also be expensive. There could be up to 10 cameras around the grand stand shooting footage. thats my 2cents

[50mxe20]

It could just be that you were watching a West Coast Eagles game and it was the players themselves that were 'fuzzy'

The were certainly fuzzy

after playing the Dockers!!