Audio keframes and rendering

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bassmannate
Posts: 7
Joined: Wed Jan 30, 2013 8:16 pm

Audio keframes and rendering

Postby bassmannate » Wed Jan 30, 2013 8:32 pm

Hello, I hope this is the right place. I wanted to post here before submitting a bug report to make sure I wasn't doing something dumb.

I'm using the VSE to edit some video I shot a few nights ago. If I don't apply any volume keyframes such as you would use to fade the audio in, the audio renders out just fine.

If I add keyframes for volume, the playback in Blender reflects the volume changes but when I render, it simply takes the value of the first keyframe for the whole clip. In this case, the volume is set to 0 at the very beginning of the clip to fade the audio in so the audio does not render out.

However, if I delete the first keyframe that sets the initial volume to 0, I can have another keyframe later in in the clip with the volume set to 1 and the audio renders out just fine as if there were no audio changes.

I also did a bit more playing with it. Out of curiosity, I moved the 0 volume keyframe up one frame and added another keyframe at the beginning of the audio clip with the volume at 1. Again, playing it in Blender, you hear the volume at full and then immediately pull back to nothing only to start fading in as it is supposed to. When rendered, the audio is at full strength for the whole clip.

If this is a bug, I will gladly submit a bug report. If I'm just being dumb, please tell me what I'm doing wrong.

mame
Posts: 6
Joined: Mon Feb 04, 2013 11:07 am

Postby mame » Mon Feb 04, 2013 11:20 am

I can't give you the answer to your problem, but I hope you can help me instead since you too are using blender as NLE for video.
When I add a clip to the timeline, and want to use the IPO-curve editor (to control volume of sound for example), I can't insert a keyframe. In the dropdown menu for 'key', the 'insert keyframe (i)' is inactive. Whatever I tried, I cant seem to get it work. Some tuts mention ctrl-LMB to insert a keyframe, but that doesn't work either. Any help would be much appreciated.

Many thanks.

mame
Posts: 6
Joined: Mon Feb 04, 2013 11:07 am

sound control in VSE using graph editor (keyframes)

Postby mame » Mon Feb 04, 2013 3:21 pm

OK, I discovered it myself. Hover over the object you want to modify. In the case of sound volume, position the playhead (green indicator in the timeline) where you want the volume to start changing, hover the mouse over the volume in the N-panel (properties of the soundstrip: right-click the soundstrip, press 'n', expand 'sound') and while hovering press 'i' (insert keyframe). You'll notice that the volumecontrol has changed color. Relocate the playhead to another point on the timeline, repeat what you just did (hover over volume, etc. ) and the color of the volume will have changed color again. Now, notice the graph-editor: a pink line has appeared, with little dots at the place where you inserted the keyframes. rightclick on these dots and drag and the line will change accordingly. Voila, volume control at your fingertips.
If anyone still has a hard time figuring this out (like I did) let me know and I'll make a short video about it to show you.

bassmannate
Posts: 7
Joined: Wed Jan 30, 2013 8:16 pm

Re: sound control in VSE using graph editor (keyframes)

Postby bassmannate » Wed Feb 20, 2013 6:26 pm

mame wrote:OK, I discovered it myself. Hover over the object you want to modify. In the case of sound volume, position the playhead (green indicator in the timeline) where you want the volume to start changing, hover the mouse over the volume in the N-panel (properties of the soundstrip: right-click the soundstrip, press 'n', expand 'sound') and while hovering press 'i' (insert keyframe). You'll notice that the volumecontrol has changed color. Relocate the playhead to another point on the timeline, repeat what you just did (hover over volume, etc. ) and the color of the volume will have changed color again. Now, notice the graph-editor: a pink line has appeared, with little dots at the place where you inserted the keyframes. rightclick on these dots and drag and the line will change accordingly. Voila, volume control at your fingertips.
If anyone still has a hard time figuring this out (like I did) let me know and I'll make a short video about it to show you.

Thanks for this. I'm going to try it later today to see if it works for me. I need to check these forums more often!

bassmannate
Posts: 7
Joined: Wed Jan 30, 2013 8:16 pm

Re: sound control in VSE using graph editor (keyframes)

Postby bassmannate » Wed Feb 20, 2013 8:53 pm

bassmannate wrote:
mame wrote:OK, I discovered it myself. Hover over the object you want to modify. In the case of sound volume, position the playhead (green indicator in the timeline) where you want the volume to start changing, hover the mouse over the volume in the N-panel (properties of the soundstrip: right-click the soundstrip, press 'n', expand 'sound') and while hovering press 'i' (insert keyframe). You'll notice that the volumecontrol has changed color. Relocate the playhead to another point on the timeline, repeat what you just did (hover over volume, etc. ) and the color of the volume will have changed color again. Now, notice the graph-editor: a pink line has appeared, with little dots at the place where you inserted the keyframes. rightclick on these dots and drag and the line will change accordingly. Voila, volume control at your fingertips.
If anyone still has a hard time figuring this out (like I did) let me know and I'll make a short video about it to show you.

Thanks for this. I'm going to try it later today to see if it works for me. I need to check these forums more often!


Oops, just re-read it more carefully now that I have a chance to try it. This is exactly how I'm adjusting volume. When I play back in Blender, it reflects the audio keyframes but when I render out, it does not. It usually picks up what ever the first keyframe is. So, if I have audio fading in, it will pick up on the first keyframe which is volume at 0. Likewise, if a clip has audio fading out as the first thing I do to it, the first keyframe the render engine will encounter is one that has the volume at 1 and so will apply that level to the entire clip.

mame
Posts: 6
Joined: Mon Feb 04, 2013 11:07 am

Postby mame » Wed Feb 20, 2013 10:36 pm

I took a little video clip and made a roler coaster of audio levels using the technique described previously. When I rendered it out, the movie played back just fine with the soundlevels I made (louder, softer, louder again, fade out). The one thing you need to do though, is to make sure that apart from choosing a video format to render with (in the N-panel), you need to choose an audio codec as well (just below the video format; standard set to no codec = no sound). Maybe that's what went wrong in your case?

bassmannate
Posts: 7
Joined: Wed Jan 30, 2013 8:16 pm

Postby bassmannate » Thu Feb 21, 2013 3:16 am

mame wrote:I took a little video clip and made a roler coaster of audio levels using the technique described previously. When I rendered it out, the movie played back just fine with the soundlevels I made (louder, softer, louder again, fade out). The one thing you need to do though, is to make sure that apart from choosing a video format to render with (in the N-panel), you need to choose an audio codec as well (just below the video format; standard set to no codec = no sound). Maybe that's what went wrong in your case?


Nope. I've got AAC selected. I did a bit more research and this ONLY happens when I render out in Quicktime format. Ironically, 99% of what I use my videos for needs to be in Quicktime.

I guess I could render out in something else and then convert? I just don't want to take a hit in quality by doing that.

mame
Posts: 6
Joined: Mon Feb 04, 2013 11:07 am

Postby mame » Thu Feb 21, 2013 8:45 am

That's strange...I'll look into that later today. The test render I did was in video codec H.264 and audio codec MP3, which worked fine. Did you try render Quicktime with MP3 audio instead of AAC? Maybe the AAC codec could be buggy?

bassmannate
Posts: 7
Joined: Wed Jan 30, 2013 8:16 pm

Postby bassmannate » Thu Feb 21, 2013 2:20 pm

mame wrote:That's strange...I'll look into that later today. The test render I did was in video codec H.264 and audio codec MP3, which worked fine. Did you try render Quicktime with MP3 audio instead of AAC? Maybe the AAC codec could be buggy?


Yup. Just seems to be something about the Quicktime MOV format.

mame
Posts: 6
Joined: Mon Feb 04, 2013 11:07 am

Postby mame » Fri Feb 22, 2013 9:42 am

Indeed some video formats seem to be buggy, but I found a workaround for you by using the Xvid format - see image. On my system, this produced a QuickTime .mov file with proper sound levels.

Image

The core team should definitely look into the codec problem, but at least you will be able to deliver your work. Are you going to post a bug report?
HTH!

bassmannate
Posts: 7
Joined: Wed Jan 30, 2013 8:16 pm

Postby bassmannate » Mon Feb 25, 2013 3:28 am

mame wrote:Indeed some video formats seem to be buggy, but I found a workaround for you by using the Xvid format - see image. On my system, this produced a QuickTime .mov file with proper sound levels.

Image

The core team should definitely look into the codec problem, but at least you will be able to deliver your work. Are you going to post a bug report?
HTH!


Wow! Thanks! I never would have thought of trying Xvid. I'll have to try this Tuesday when I'm at the office.

I thought I had submitted a bug report but now I can't seem to find it. I'll do a bit more searching and if I can't find it, I'll assume that something happened when I pressed the submit button and repost.

mame
Posts: 6
Joined: Mon Feb 04, 2013 11:07 am

Postby mame » Mon Feb 25, 2013 11:41 am

A word of caution though, you might want to stick to version 2.65 and keep away from v.2.66. I wasn't able to output to QuickTime in 2.66 at all. There is an earlier bugreport concerning rendering to QuickTime. See thread below:

http://projects.blender.org/tracker/?func=detail&atid=498&aid=32274&group_id=9

You appearently rely on codecs already installed on your system in the newer version.

Good luck!

bassmannate
Posts: 7
Joined: Wed Jan 30, 2013 8:16 pm

Postby bassmannate » Thu Feb 28, 2013 2:16 am

mame wrote:A word of caution though, you might want to stick to version 2.65 and keep away from v.2.66. I wasn't able to output to QuickTime in 2.66 at all. There is an earlier bugreport concerning rendering to QuickTime. See thread below:

http://projects.blender.org/tracker/?func=detail&atid=498&aid=32274&group_id=9

You appearently rely on codecs already installed on your system in the newer version.

Good luck!


Just wanted to update this. Tried it today and it worked great. Still in 2.65a but I was able to get the render engine to recognize the volume keyframes.


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