FF103 - This one's not too awkward. You have an Imagination Slideshow exported at NTSC 720 x 480, that you need to convert to smaller display and filesize, for web use, while keeping good picture quality and stereo audio.
> We've been converting Imagination PAL 720 x 576 exports for the kids' hand-helds for some time, here. The procedure for NTFS is the same, although you'll get approx 320 x 240, instead of our 320 x 256.
> Converting MPEG2 directly to FLV tends to give a choppy and pixellated result.
> You're needing a conversion to FLV, so the Stage-1 AVI version doesn't matter. However, while Xvid4 is the best conversion format, if needed to play in hand-helds, check that they will play Xvid4. If not, then use MPEG4.
> You need to reduce the playback size and filesize, so make the first conversion to Xvid4, using Avidemux.
> Drop your Slideshow into the Avidemux window. It will ask if you want the mpeg indexed - say Yes.
> Check with the slider at the bottom that your Slideshow is present and correct.
> Change "Video" to Xvid4 (MPEG4 ASP Xvid.)
> Go to "Configure" and change the Encoding Mode to "Average Bitrate - 2-Pass". (The First Pass allows Avidemux to "map" the video, and keep the Audio in Sync, etc, on the Second Pass.)
> Then go to "Filters" and click on "Mplayer Resize". In the dialog that appears, your NTSC video should show as 720 x 480. The "Lock Aspect Ratio" box should be ticked. Now tick the "Nearest Multiple of 16", box.
> Move the slider to the Left - until the higher number is at 320. The lower number in your NTSC case will be about 240. For web (or on PC) an exact "240" isn't essential - but that the X/Y Error numbers are at 0.00, is. When correct, change "Resize Method" from Bilinear to Lanczos3. (Very slightly slower, but a better conversion mode.) Click "OK" - and check the Resize info in the right panel. Close the dialog.
> Your MPEG2 Audio will be at 48000 - so under Audio, select "MP3 (lame)". Then under "Filters", check the "Resampling" box, and make the number in the field 44100. (Correct for AVI and FLV.)
> Make sure that the "Format" at the bottom says "AVI".
> Make a directory (folder) on the Desktop as Output Destination. Now click the "floppy-disk" icon on the bar, and browse to it. Give the video output a name with extension *.avi, and click "Save".
> When the task completes, check the resulting video - SMplayer or VLC are okay for that.
> Close Avidemux and re-open it. Drop the Videoname.avi into the window. Select under "Video" - "FLV1 (lavc)."
> Under "Audio" select "MP3 (lame)", then again set "Filters" - "Resampling" to 44100.
> At the bottom, ensure that output "Format" says "FLV".
> Run the conversion as above, Saving to a suitable Destination directory.
>> In a sample conversion I did while checking the stages for the above - the original Imagination file was 76.1MB, the Xvid4 file was 25.5MB, and the FLV file 11.9MB. Video quality good, Stereo Audio retained. See Pic - the Desktop icons show scale.
> Any questions - post back - saying at what stage any problem seems to be.
Regards, Dave.
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