Charles Simonson
Forum Replies Created
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Apple has a pretty good MPEG-2 encoder in Compressor 2, and at that data rate, it should be able to produce nice results. One of the reasons why you may not want to use that high of a data rate though, is because some DVD players can not handle the rate on recorded DVD-Rs. So, if you are seeing lots of artifacts, especially at transition scenes, where the bit rate can spike, then it could be the DVD player and not the actual encode. Typically, very high-quality SD MPEG-2 encoding can be achieved at rates around 6.5mbps with most decent software encoders these days. And it is very doubtful that 2 pass encoding “introduced” the choppiness.
Another issue may be if your source is interlaced. If you are planning the disc for playback with a television, it is best to leave the encode interlaced. If you are only going to watch the disc on a computer though, then deinterlacing may help in improving quality (not always though).
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Apple’s MPEG-4 Part 2 encoder is not that great. The MPEG-4 encoder included with Popwire’s Compression Master 3 is the best software MPEG-4 encoder anywhere in terms of quality and one of the fastest as well. CM3 can also preserve timecode for your encodes.
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I would try using Elementary streams from Compression Master rather than Program muxed streams when encoding. But since you already have some files encoded, I would suggest opening your MPEG-2s in an app called MPEG StreamClip (free) and choose the “Demux to M2V and M1A” option. Then use those elementary streams in DVD Studio Pro. If there was an error in the way Compression Master muxed the two streams, then it should be fixed when they are demuxed with MPEG StreamClip.
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Sorry, but 16:9 does not mean “indicative of at least 720 resolution which is HD”. When you buy a DVD, the PAR is usually anamorphic 16:9, yet it is not 720p, it is only 480p. This is what is meant by the Apple preset in Compressor 1. Compressor 1’s MPEG-2 encoder presets are targeted only towards standard DVD output. As I have stated before, the encoder in Compressor 1 and QT6 is only capable of 480p max output, no matter what the input resolution of the source is. Trust me on this and if you don’t, please stop writing on here and go and encode for yourself to check this out. As far as FCP, there is no ambiguity, it can certainly output HD, but this refers to output of HD over SDI using an appropriate capture board or to an appropriate export format. MPEG-2 was not an “appropriate” export format for FCP in versions before 5 (at least not directly with Apple’s products). What you can do is export your HD project from FCP to a HD source file using a different codec that is more resolution independent.
On the ATSC front, two of the resolutions you noted are for SD (there are actually a few more formats, but no need to worry about those right now). I can’t remember right now if QT6 or Compressor 1 supported output to the fixed pixel size 704×480 or 640×480, but they may have. If you have a 16:9 HD source, and are looking to encode to an ATSC format with Compressor 1, then see if 704×480 (sometimes referred to as EDTV) is an option. Also, ATSC as it is today can be broadcasted at right around 8Mbps for 720p. FOX does this for some of their programs, but mostly they broadcast at 9Mbps. At 1080i, I have seen HBO broadcast at 10Mbps, but usually 11Mbps (on the flip side, TNT broadcasts at about 18Mbps). These numbers will continue to get lower and lower as further advances are made to compression with MPEG-2 (although they are very close today to what the maximum can be achieved with MPEG-2 and low bit rate encoding).
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Right, those settings are for a 16:9 anamorphic 480p encode. Notice how resolution isn’t specified there. Its not that Compressor 1 will do a bad job encoding your material, its that it won’t encode it to HD to begin with. Also, even if it could encode MPEG-2 at HD resolution, Compressor 1’s output quality would be terrible at the average bit rate of 6.8 (this doesn’t even take into account the fact that the MPEG-2 encoder from Apple has made huge strides from Compressor 1 to 2) as 6.8Mbps is too low for MPEG-2 HD (1080i or p). Fact is, Apple didn’t support HD MPEG-2 encoding until Compressor 2. Compressor 1 and previous versions of the QT MPEG-2 export component only supported a max resolution of 480p and a max bit rate of 9Mbps.
I can’t understand why this hard for you to grasp. The easiest thing to do would be to do some short sample encodes and determine this yourself. Simply grab or edit a 10 second source clip and use that to test your MPEG-2 encodes with.
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1: Compressor 1 did not encode to HD resolutions with MPEG2. So that is a major difference between Compressor 1 and 2.
2: Yes, there can be. The MPEG formats have various profiles and levels that are supported to ensure a video will play back correctly on a certain platform/device. Apple’s encoder only supports a few of the profiles/levels. The MainConcept encoder can support them all.
There are many variables that can make a stream incompatible with one device or decoder to another. It is best to know and understand the required specifications that you will need to encode to in order to ensure proper playback. The page you linked to in your previous post does a good job explaining these. And the streams that come out of Compressor for MPEG2 are usually elementary streams. This means the audio and video are separate and not muxed. You can easily mux the tracks together into a program or transport stream using some of the freeware tools on the mac. A program stream should have broad compatibilty, whereas a transport stream may not as the specifications for the types supported are more specific.
Feel free to email me if you wish.
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Make sure the tracks have video and audio associated with them. Because you have both AIFF and AC3, its possible DVDSP could have got confused as to which one to use and so it chose neither. This is probably better asked on the DVDSP forum.
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First of all, the current installation and location of Flip4Mac should be fine for Cleaner 6.5. And accessing F4M should be about the same as it was with Cleaner 6. All you need to do is go to the settings, click the Output tab, then click the Format pull down list, and select the format that says “Windows Media”. Note that Cleaner’s built in encoder says “Windows Media 7”, as it hasn’t been updated in quite some time. Honestly though, if you are interested in F4M and a compression suite, I would recommend Squeeze 4 or Compressor 2. Compression Master 3 is another option but they use their own WMV9 encoder.
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Q1: Not sure; if it understands all MPEG-2 HD Program streams, you should be in luck with just Compressor. If it only understands raw ATSC MPEG-2 Transport streams, then you may need some help with another app (as I mentioned before, MainConcept; MPEG StreamClip can also take Program streams and mux them into transport streams, so that may work as well). I don’t have either a XBox 360 or Media Center 2005 PC, so I can’t say for certain.
Q2 and Q3: This I am pretty positive it will. The signal being sent to the display is not considered a computer signal any more than the signal from an HD DVR is considered a computer signal. The analog HD signal your display receives will behave the same as if it came from an HD cable or ATSC STB. Again, my setup is pretty similar except that I use a mac to serve and STB from IOData and JVC to display on my TV. The signal interpretation through the IOData is no less or no greater than if I were using an HD DVR box like the one from Cox cable.
With the uncertainty of it all, I would suggest either purchasing the equipment and trying it yourself (shouldn’t set you back too much, and if it doesn’t work, you could always return everything) or do what I do and not worry about throwing the PCs into there and stay with the mac by getting a device like the IOData. If you have pletnty of space in your home directory, you could be up and running for less than $250.
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From what I understand, and correct me if I am wrong, the XBox 360 can play back HD MPEG-2 and WMV streams that are stored on a Media Center 2005 PC. When that is displayed, it is displayed at the native resolution plus or minus the resolution that you have the XBox 360 connected to your display. So, if you have 720p stream, and connect to a 720p display through the HD output of the XBox, then you should be viewing the true resolution of the stream. I know the XBox 360 will not upconvert however, so DVDs and other 480p content is only fitted and scaled to match the output resolution.
As far as making these streams, that could be tricky depending on what the Media Center and XBox wants. If, by MPEG-2 HD, MS only means ATSC transport streams are supported, then I don’t think Compressor will be able to provide this. If they mean that any MPEG-2 HD Program stream is supported, then Compressor should be able to help. If you need to make ATSC compatible transport streams, then the MainConcept stand-a-lone encoder is great for this.
Another option if all you are looking to do is connect a STB to a computer and stream content to a TV is to get a networked HD DVD player like the one from IOData ($299) or JVC ($399). I have both of these, and I also have a couple of EyeTV 500’s and a EyeTV 200. I capture a lot of ATSC and Clear QAM content, and then stream it over my network using ElGato’s EyeConnect software ($100; the STBs come with their own software to network with as well, but the mac versions do not support sharing folders outside of the user’s home directory) to the players, and watch HD all day long. It also works great for encoding my own content in HD with Windows Media and MPEG-2 and then using the STB as the play back device. And because the STBs have hardware decoders on them, I don’t have to worry about dropped frames as long as the bitrate of the encode is under 25Mbps and my network isn’t too busy with other traffic.