Options when adding a movie strip in the Video Sequence Editor

When adding a movie strip the number of Start Frame is automatically added. I noticed is never at 0 or 1, is always some random number, and now is showing a negative number too. Is there a way to figure out how blender chooses the starting frame? I know I can just hit reset and it will go back to 0, but just wondering if anyone knew how this number is added or controlled.

Another question is about the “Replace Selection” check. I don’t know what it does and I have looked everywhere. At first I thought it meant to swap the selected strip with another one, also I thought that it might be related to the blend mode in which the movie will be played. But all movie strips are added with the cross blend by default, not with the replace blend.

Thanks :slight_smile:

The start frame is the last place your cursor was located when you clicked add! Not terribly helpful.

I think that the replace function allows the new strip to occupy the same space as the one thats already there. But I could be wrong.

Thanks for your answer 3pointEdit. I’m watching your amazing tutorials btw :slight_smile:
I had to dig some source code and rely on my rusty c skills and I found this about replace selection.

00674 if (RNA_boolean_get(op->ptr, “replace_sel”)) {
00675 deselect_all_seq(scene);
00676 seq_active_set(scene, seq);
00677 seq->flag |= SELECT;

So it basically makes the new strip selected or unselected when added to the VSE. Is kind of confusing because the use of the word “replace”, since there is a “replace” blend mode. Instead of repeating the name of the option in the tooltip, it should say something like “Check this option if you want to make the new strip selected in the VSE. Un-check this option if you want the new strip not to be selected when added to the VSE”. But this is too long I figure. Funny I found this comments about “Replace Selection” in the source code too.

00670 /* not sure if this is needed with update_changed_seq_and_deps.
00671 * it was NOT called in blender 2.4x, but wont hurt */

Thanks again.

Hmm, good find. I would call it Activate Strip, not replace. But I would suggest submiting a bug in the tracker as it seems quite redundant.