C# and brightness control

[lallous]

Hello

I have used the VLC / C# binding from the Wiki and created a small sample:

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private void button1_Click(object sender, EventArgs e) { try { video1.ClearPlayList(); video1.AddToPlayList(@"W:\Office.wmv", "Something", new string[] { }); video1.Play(); } catch (Exception ex) { MessageBox.Show(ex.Message); } }

I created another button for controlling brightness while the moving is playing:

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private void button1_Click_1(object sender, EventArgs e) { video1.Brightness = float.Parse(textBox1.Text); Text = video1.Brightness.ToString(); }

I know the brightness range is from 0.0 to 2.0 with default value of 1.0.

Now why when I set the brightness with this code, still it is value is 1.0 ? As if it is unchanged?

Can you please tell me how to set brightness correctly?

Thanks,
Elias

[lallous]

Hi again,

It turned out after investigation that:

VlcObject vobj = new VlcObject(this.vlcHandle, objectType)

Is not initializing / returning a valid subobject, thus:

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public float GetVlcObjectFloat(ObjectType objectType, String propertyName, float errorReturn) { try { using(VlcObject vobj = new VlcObject(this.vlcHandle, objectType)) { vlc_value_t floatValue = new vlc_value_t(); if((vobj.SubObject != IntPtr.Zero) && (VlcError.Success == __var_Get(vobj.SubObject, propertyName, ref floatValue))) { return floatValue.f_float; } } } catch(Exception ex) { this.lastErrorMessage = ex.Message; } return errorReturn; }

using(VlcObject vobj = new VlcObject(this.vlcHandle, objectType))
It will create a vobj, but the vobj.subObj is always NULL

Looking further inside:

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public VlcObject(int vlcHandle, ObjectType objectType) { vlc = vlc_current_object(vlcHandle); if(IntPtr.Zero != vlc) { if(objectType == ObjectType.VLC_OBJECT_VLC) { subObject = vlc; } else { subObject = __vlc_object_find(vlc, objectType, ObjectSearchMode.FIND_CHILD); } } }

The __vlc_object_find() call isn't returning what is needed.

Please advise on how to properly use these functions and/or what is wrong with accessing those VLC variables?

[lallous]

Hi Readers,

After a long day of research and debugging and getting to learn about VLC more, it turned out that the "adjust" video out filter must be loaded before you can access the "brightness" variables.

For that, you have to pass an option to VLC when adding the media file.

Initially, I tried to add the option as:

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video1.AddToPlayList(@"W:\Office.wmv", "Something", new string[] { "--vout-filter=adjust" });

But nothing happened...

I took a look at LibVlc.cs instead and say it has a AddTarget() that actually causes VLC to load the libadjust filter properly.
For that, I hacked the NativeVlc and mixed some of LibVlc into it, this is the quick hack, which ofcourse can be incorporated better later on:

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video1.Native().AddTarget2(@"w:\office.wmv", new string[] { ":vout-filter=adjust" });

Now, the "brightness" variable is there and I can control it using the initial code.

Hope that is of help,
Elias

[jleroux61]

Where did you post your hack?
Thanks
Jean

[lallous]

My hack was posted here.

Just when adding a video to the playlist, make sure you pass an option to tell VLC to load the adjust filter, exactly as my last post demonstrates.

HTH
Elias