[Recovered Thread: 72782]

[tclune]

Let me just warn you about taking the samples from the manufacturer's website as indicative of the quality that you can expect. Remember that this is a marketing document. If, for example, the compression falls apart when applied to "blend" style scenes (gradients in the sky, etc), the sample videos will simply steer clear of these situations. Real-world sound ALWAYS is terrible on videos, but not on the clips you'll get from the manufacturer's website. Most video on still cameras can't zoom, and some can't even refocus, within a clip. So the scenes in the clips will be constructed to make that fact irrelevant. And so on. You are much better served if you can see sample clips from actual users. They won't have the skill (or generally the interest) to hide the warts from you.

[Caelum]

Phil999 wrote:

[...]I see that the Olympus C-770 also uses MP4 compression but have not yet found any sample movies.[...]

You meanother thanthe ones right here on Steve's digicams, right? (there's both a .MOV and a .MP4):G

[Phil999]

Thanks

I am new to this site and only just finding my way around so missed the clips for the C-770.

The MOVclip looks fine but the MP4 one, although nice and compact, looks slightly greyish. I am not sure if this is due to the settings or a result of the MP4 compression. Any thoughts ?

Since one reason for replacing my old Olympus 490-Z is the very poor video quality, partiallycaused by compression blockiness I am sure, I suppose I am a little suspicious of Olympus.

Phil

[Caelum]

Phil999 wrote:

[...]The MOVclip looks fine but the MP4 one, although nice and compact, looks slightly greyish. I am not sure if this is due to the settings or a result of the MP4 compression. Any thoughts ?[...]

I'm not sure about greyish, perhaps blueish?To me that MP4 sample lookssmeary and"blocky", especiallywhen viewed full screen.

[Phil999]

Just been checking the sample movies on this site for the "other" MP4 camera - the Sanyo C5. They also seem to suffer from the same "greyish" effect.

Maybe this is a feature of MP4 compression. I noticed that the sample on the Japanese Sanyo site at

http://www.sanyo-dsc.com/english/pro.../image_sample/

Which looking excellent, has colours which perhaps tend to mask this effect.

At the moment I am favouring the Fuji Finepix S7000.

Cheers Phil

[Caelum]

Phil999 wrote:

Just been checking the sample movies on this site for the "other" MP4 camera - the Sanyo C5. They also seem to suffer from the same "greyish" effect.[...]

Wow, it's interesting because I didn't see that... but then I decided to try Quicktime 7 on WindowsXP to view the .MP4 files and they are washed out, or "greyish"!? Quicktime appears to be significantly reducing the contrast. I'm using media player classic and when I play.MP4 videos they have full contrast, it looks really quite different from what I see in QT7. Also, ifyou convert an .MP4 to an .AVI utilizing MP4Cam2AVI you should see the same difference. I looked at the available settings in QT7 and can't find controls to change the video's appearance?

Ok... I was able to take a screenshot of both to demonstrate the difference, these are actual screenshots, cropped and pasted together, only text added, no other modifications:

[Phil999]

Yes, the difference is interesting.

What did you install to get Media Player Classic to play MP4 files. This is my player of choice but I cannot play MP4 and when it searched for a codec it could not find one. I have to use my Quicktime 6.5 to play MP4s

Another mystery I have at the moment is the format of the alleged Sanyo C5 files at

http://www.unmediated.org/archives/2...ted_sany_1.php

The movie samples shown there are MOV files not MP4 files. These do play on my Media Player classic so do not appear to be MP4 files in disguise.

Phil

[Caelum]

I think I re-installed Media Player Classic after Quicktime 7, so perhaps it seeked out and picked up the necessary codecs from Quicktime at that time. There is something called "Quicktime Alternative" out there that includes MPC and the Quicktime codecs without Quicktime itself.

Edit: oh, and according to QT those unmediated .MOV files do contain MPEG-4 video, so I think whatMPC ismissing is the .MP4 demuxer.

By the way, here is another example of the difference when playing an .MP4:

[Phil999]

Hi Caelum

I downloaded the MP4Cam2AVI program ( Very useful ) and converted the Sanyo C5 & the Olympus C-770 MP4 Sample Moviesto AVI.

I am now able to view these on my Media Player Classic ( MPC ) and compare them with the original MP4 files viewed on Quicktime 6.5 ( QT )

I have also convertedto AVI the Xacti C5files, which are inMOV format at

http://www.unmediated.org/archives/2...ted_sany_1.php


The MOV files from the abovesite and the converted AVI files are both playable on my MPC and the AVI ones are much more vivid and brighter.

I can compare the same MOV files, from my current Oly 490Z, on QT and MPC and they show a slight improvment on MPC.

I would have posted some screen captures of the MOV & AVI movies but have just discovered that you cannot do a screen capture of an AVI file plaused in a player such as MPC - puzzling, must investigate this further.

So, from my experiments, it seems that there is a slight improvement playing on MPC rather than QT buta much greater enhancement from the convertion of the MP4 files to AVI by Mp4Cam2AVI.

I noticed after I converted the MP4 & MOV files with MP4Cam2AVI,that "DivX" is shown on the bottom of the movie at the start. thatRADTools file-info show them as DirectShow files and that GSPOT indicates the codec to be DivX.

So, does not this mean that the files are actually being recoded rather than just repackaged.

I had drawn the conclusion that I should not consider either the Sanyo C5 or the Olympus C-770 any further because of the "poor colour quality" they produced. It now seems that this can be corrected.

I wonder just how many people will beviewing the MP4 files on QT to evaluatethese cameras and will be reaching an erronious conclusion,as I originally did.

I found an article from aGoogle search about QT & PCs & dull grey movies.

http://groups.google.com/groups?hl=e...a=N&tab=wg

Sorry the above did not copy as a hyperlnk - not sure why. I do not seem to havethe "Hardware" setting, which the article refers to in my QT.

Thanks again for the tip about MP4Cam2AVI.

Look forward to your further comments.

Phil

[Caelum]

Ok, MP4Cam2AVI does not convert the video, it only copies the video stream into an AVI file, then it puts the DX50 fourcc code in the header simply to tell players to use the Divx MPEG-4 codec to handle the stream. MP4Cam2AVI can directly copy the AAC audio, or it can convert the audio to another codec in caseyou don't have an AAC codec on your PC. So, as far as the video goes, MP4Cam2AVI does not interfere or change it (except for optional special handling of "frozen frames", which don'tappear to happen with Sanyo's streams). When you play an MPEG-4.MOV or .MP4 withMedia Player Classic, Apple's codecs are still utilized, when you play an MPEG-4 .AVI, then it's Divx, or whichever codec you choose (try advanced settings in MP4Cam2AVI) that are utilized, depending on the fourcc. Besides, MP4Cam2AVI would not be able totranscode video at 30x realtime even if it wanted to.

The reason you weren't able to screen capture with Media Player Classic is that by default it utilizes the defaultvideo renderer, which typically is the video overlay. The video overlay is not actually part of the current screen, but rather, as it's name implies, it's a hardwareoverlay.If youchange Media Player Classic's output renderer (View->Options->Playback->Output) to DirectX7 (VMR7) or DirectX9 (VMR9), then you can take screen captures. There are debates as to which renderer is best for everyday use, but basically it depends on the capabilities of your graphics card.

Thanks for that link, I only found a "Safe Mode" in QT7 that doesn't use hardware acceleration. It appears to have better contrast but CPU usage jumps to rediculous levels.