Re: [flexcoders] playing two video simultaneously, seeking too slow especially when playing from dvd
On Monday 22 January 2007 17:43, Benjamin Schwehn wrote: The two FLV typically have sizes between 20 and 200MB each. One is encoded with an Flash 7 Codec, the other with the newer Flash 8 On2 VP6 Codec. (seeking is slow with both codecs) Would it be possible to just join the two video files together off line and ship that on the DVD ? Obviously, if you have hundreds of videos on the disk that can have any two combined, this isn't going to work. -- Tom Chiverton Helping to biannually target killer paradigms This email is sent for and on behalf of Halliwells LLP. Halliwells LLP is a limited liability partnership registered in England and Wales under registered number OC307980 whose registered office address is at St James's Court Brown Street Manchester M2 2JF. A list of members is available for inspection at the registered office. Any reference to a partner in relation to Halliwells LLP means a member of Halliwells LLP. Regulated by the Law Society. CONFIDENTIALITY This email is intended only for the use of the addressee named above and may be confidential or legally privileged. If you are not the addressee you must not read it and must not use any information contained in nor copy it nor inform any person other than Halliwells LLP or the addressee of its existence or contents. If you have received this email in error please delete it and notify Halliwells LLP IT Department on 0870 365 8008. For more information about Halliwells LLP visit www.halliwells.com. -- Flexcoders Mailing List FAQ: http://groups.yahoo.com/group/flexcoders/files/flexcodersFAQ.txt Search Archives: http://www.mail-archive.com/flexcoders%40yahoogroups.com Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/flexcoders/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/flexcoders/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [flexcoders] playing two video simultaneously, seeking too slow especially when playing from dvd
Hi, 1. Is it possible to force the flash player to just load both videos into main memory (or PageFile) at start up? You can set the buffer-time to a large number, I suggest don't keep it too large. Should work fine on the cost of more memory consumption... Read more about bufferTime in Flex docs. You can also make it more -abdul On 1/23/07, Tom Chiverton [EMAIL PROTECTED] wrote: On Monday 22 January 2007 17:43, Benjamin Schwehn wrote: The two FLV typically have sizes between 20 and 200MB each. One is encoded with an Flash 7 Codec, the other with the newer Flash 8 On2 VP6 Codec. (seeking is slow with both codecs) Would it be possible to just join the two video files together off line and ship that on the DVD ? Obviously, if you have hundreds of videos on the disk that can have any two combined, this isn't going to work. -- Tom Chiverton Helping to biannually target killer paradigms This email is sent for and on behalf of Halliwells LLP. Halliwells LLP is a limited liability partnership registered in England and Wales under registered number OC307980 whose registered office address is at St James's Court Brown Street Manchester M2 2JF. A list of members is available for inspection at the registered office. Any reference to a partner in relation to Halliwells LLP means a member of Halliwells LLP. Regulated by the Law Society. CONFIDENTIALITY This email is intended only for the use of the addressee named above and may be confidential or legally privileged. If you are not the addressee you must not read it and must not use any information contained in nor copy it nor inform any person other than Halliwells LLP or the addressee of its existence or contents. If you have received this email in error please delete it and notify Halliwells LLP IT Department on 0870 365 8008. For more information about Halliwells LLP visit www.halliwells.com. -- Flexcoders Mailing List FAQ: http://groups.yahoo.com/group/flexcoders/files/flexcodersFAQ.txt Search Archives: http://www.mail-archive.com/flexcoders%40yahoogroups.com Yahoo! Groups Links
Re: [flexcoders] playing two video simultaneously, seeking too slow especially when playing from dvd
Tom Chiverton wrote: On Monday 22 January 2007 17:43, Benjamin Schwehn wrote: The two FLV typically have sizes between 20 and 200MB each. One is encoded with an Flash 7 Codec, the other with the newer Flash 8 On2 VP6 Codec. (seeking is slow with both codecs) Would it be possible to just join the two video files together off line and ship that on the DVD ? We considered that option, but would like to avoid it because the videos are not at the same resolution (neither same framerate, but that would be less of a problem): Video 1 (typically a lecturer giving a speech) is at 320x240, video 2 (typically PPT Slides, Animations, Films) is at 640x480. Since a joined video must still be rectangular, it would get quite large, at least 980x480, but in fact even a bit bigger (ca 1040x480, since we would need some additional space for our layout (the two videos shouldn't be right next to each other). Those videos would possibly be a bit of a hassle to generate and handle (and probably quite a bit larger because of the empty space and because we'd have to use the higher framerate for both videos). Escpecially as it is a bit of a hassle putting controls on top of a VideoDisplay, which we would have to do to for design reasons. I'm a bit surprised really, that Flash can't seek forward just a bit faster once the FLVs are a bit bigger and better quality than the stuff on YouTube etc. Thanks Ben -- Flexcoders Mailing List FAQ: http://groups.yahoo.com/group/flexcoders/files/flexcodersFAQ.txt Search Archives: http://www.mail-archive.com/flexcoders%40yahoogroups.com Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/flexcoders/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/flexcoders/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [flexcoders] playing two video simultaneously, seeking too slow especially when playing from dvd
Depends, if you are streaming FLVs using Flash Media Server or Red5, you can do the seek thingy...It's quite cool... But if it's progressive, it all depends on how much video is downloaded, how much it is buffered, how big the video is.. Generally seek algorithms are kindda complex.. Also depends on video encoding, bitrate etc... One of my colleagues has been doing some research on different ways to buffer progressive videos...he has come up some algos, I would see if I can share that with you, no promises though... Since you are going do deliver your project on optical-disc, it's not about downloading from internet.. I am sure you can do much better here... just keep trying different things (playing with numbers, encoding options etc)... -abdul On 1/23/07, Benjamin Schwehn [EMAIL PROTECTED] wrote: Tom Chiverton wrote: On Monday 22 January 2007 17:43, Benjamin Schwehn wrote: The two FLV typically have sizes between 20 and 200MB each. One is encoded with an Flash 7 Codec, the other with the newer Flash 8 On2 VP6 Codec. (seeking is slow with both codecs) Would it be possible to just join the two video files together off line and ship that on the DVD ? We considered that option, but would like to avoid it because the videos are not at the same resolution (neither same framerate, but that would be less of a problem): Video 1 (typically a lecturer giving a speech) is at 320x240, video 2 (typically PPT Slides, Animations, Films) is at 640x480. Since a joined video must still be rectangular, it would get quite large, at least 980x480, but in fact even a bit bigger (ca 1040x480, since we would need some additional space for our layout (the two videos shouldn't be right next to each other). Those videos would possibly be a bit of a hassle to generate and handle (and probably quite a bit larger because of the empty space and because we'd have to use the higher framerate for both videos). Escpecially as it is a bit of a hassle putting controls on top of a VideoDisplay, which we would have to do to for design reasons. I'm a bit surprised really, that Flash can't seek forward just a bit faster once the FLVs are a bit bigger and better quality than the stuff on YouTube etc. Thanks Ben -- Flexcoders Mailing List FAQ: http://groups.yahoo.com/group/flexcoders/files/flexcodersFAQ.txt Search Archives: http://www.mail-archive.com/flexcoders%40yahoogroups.com Yahoo! Groups Links
Re: [flexcoders] playing two video simultaneously, seeking too slow especially when playing from dvd
Abdul Qabiz wrote: Hi, 1. Is it possible to force the flash player to just load both videos into main memory (or PageFile) at start up? You can set the buffer-time to a large number, Thanks Abdul, I entirely overlooked this property! Interestingly when setting this property to a very large value, initial load only gets slow for the film encoded with the older sorenson codec. Initial load is 90 seconds for a 70MB/23 minutes film when trying to buffer it completely (just for testing purposes) from harddrive, not dvd). I'm not sure why it takes so long, since neither CPU nor disk access time seem to be the bottleneck. The VP6 encoded film loads very fast, even when bufferTime is set to totalTime. Anyways, first tests show good results when buffering only the VP6 film. At least for small films that can be buffered entirely. Well, I guess I'll have to play around a bit more, probably re-encode all films to VP6, but this definitely helped, thanks! Generally seek algorithms are kindda complex.. Also depends on video encoding, bitrate etc... Well, I kind of thought that seeking should be very fast for constant bitrate (cbr) encoded videos. I believe the VP6 codec is alway cbr. After all, for cbr vids, it should be trivial to calculate the exact file offset for any given frame. Then readhead positioning should only take a few milliseconds for HDDs and a couple 100 ms for DVDs. For vbr things get potentially more complicated, I believe most codecs just generate a keyframe - offset table which is loaded before playback and enables fast (keyframe-) seeking. Anyways, thanks again for your help! Ben
[flexcoders] playing two video simultaneously, seeking too slow especially when playing from dvd
Hello all, Long post in a nutshell: I'm looking for a way to speed up seeking time when playing FLVs. Long post: I'm currently working on a project that displays two flv-files at the same time (playback is synchronized). Performance when seeking forward is just about acceptable (though not great) when playing from the hard drive. However -- once done -- the project will be distributed on a DVD. Here seeking performance and also the initial load is horrible, since flex tries to seek both files at the same time causing the dvd drive head to jump a lot causing very slow read times. So i have two questions: 1. Is it possible to force the flash player to just load both videos into main memory (or PageFile) at start up? 2. To perform a seek, I currently set VideoDisplay's playheadTime property. However seeking occurs asynchronously and there seems to be no good way to recieve an event once the seeking has finished, or is there? Therefore, after I set the playheadTime, I'm starting a timer to check every couple of hundred milliseconds for VideoDisplay's property 'stateResonsive' to become true. It seems that stateResponsive becomes true a bit before the seek has really finished. Therefore I also check whether the VideoDisplay's playheadTime is the same as the requested seekTime. Is there a better way to do this? Checking with a timer event seems a bit idiotic to me. Also, seeking takes quite long even when I first set playheadTime only for video 1, wait until the seek has completed, then set playheadTime for video 2, again wait until seek has completed and then restart both videos. I need to know when both videos have finished seeking, so that i can play both FLVs synchronized. The two FLV typically have sizes between 20 and 200MB each. One is encoded with an Flash 7 Codec, the other with the newer Flash 8 On2 VP6 Codec. (seeking is slow with both codecs) Or is there an altogether better way to display videos in flash rather than using the VideoDisplay control? Surely seeking shouldn't be so slow. Initial load and seeking in an similar sized avi with VLC happens almost instantaneously. Sorry about the long post and thanks for reading so far :) Ben
