New version of gui4ffmpeg missing feature that was in older version

[dlflannery]

I need the -ilme switch (preserves interlaced from input to output) to properly process some of my source mpeg2 files. This flag was available in the previous version (1.3) of gui4ffmpeg but does not work in the new version (2.0). It throws an error that "the codec does not support interlaced". However I still have the old version and it still works without throwing this error, so I know it's not because I am missing a codec on my computer.

I've been unable to find any workaround or fix for this other than to keep using the old version.

I've also been unable to find anywhere you can download the older version. If anyone else is having this problem and would like to get the older version, please PM me. I can either send it to you or, if enough people want it, perhaps we can arrange some way for VideoHelp.com to make it available as a download.

Of course if the author or another expert can provide a way to make the new version do what I want, that would be really nice!

[dlflannery]

I need the -ilme switch (preserves interlaced from input to output) to properly process some of my source mpeg2 files. This flag was available in the previous version (1.3) of gui4ffmpeg but does not work in the new version (2.0). ............... I've been unable to find any workaround or fix for this other than to keep using the old version.........................

I think I may have stumbled onto the "fix":

Instead of just "-ilme", use "-ilme mpeg2video". The "mpeg2video" is the codec name you normally would use for the conversion you are doing (in my case both input and output were mpeg2).

The ffmpeg help (type "ffmpeg -h" in a command window) showed "-ilme" under the heading:
"AVCodecContext AVOptions:", and I noticed when ffmpeg would error out it was trying to use the wrong codec (mpeg1video) for the output video stream, whereas it normally uses mpeg2video. So I guessed you now have to give the "codec context" to the -ilme switch.

Anyway it worked on a 2 minute test video, the output was interlaced, top field first, just like the input and it played OK in dgInspect. (If converted without -ilme the output becomes progressive, bottom field first, which apparently leads to the motion artifacts when played on my DVD player.)

Edit: Conversion Timings on 3GHz P4:
Source was mpeg2 edited from TiVo medium recording, 2.7 Mbps bitrate, 352x480, mpeg audio
Output to 720x480 mpeg with AC3 audio, either 3 or 4 Mbps bitrate.

Results given in percent of video length.

One result: Timings are identical for either version of gui4ffmpeg
Output Bitrate (Mbps) / -ilme used? / encoding time
3 / Yes / 116%
3 / No / 79%
4 / Yes / 121%

Conclusions:
1. Big penalty for retaining interlace: 37% of video length
2. Small price for 4 Mbps vs 3 Mbps output bitrate: 5% of video length

Note that gui4ffmpeg does include the empty NAV packets in the output MPEG, which is required by authoring programs based on DVDAuthor.

The motion artifacts without retaining interlace are not that bothersome in many cases, so you have to consider whether the extra encoding time is justified. However since you can batch a number of files through ffmpeg overnight the extra time may not be important.

Edit: See this *** thread*** on the ffmpeg forum for new developments on this topic.

[dlflannery]

I need the -ilme switch (preserves interlaced from input to output) to properly process some of my source mpeg2 files.........

I am having newly discovered problems with -ilme and with Ver. 2 of gui4ffmpeg. Please see the details in this ***post *** on the ffmpeg forum.

[dlflannery]

..............I am having newly discovered problems with -ilme and with Ver. 2 of gui4ffmpeg. ....

I've made some progress and developed some questions. See my latest ***post*** on the ffmpeg forum.