Transparent video
Last updated
Last updated
Supported file format: mp4
File size limit: within 30M
Supported video encoding format: H.264/AVC
Recommended audio coding format: LC-AAC or mp3
The main thing to note is that the transparent video here does not refer to the alpha channel in the video, but a "special" form;
Download the sample file (source: Adobe Chractor Animator software sample: lower limb rehabilitation robot)
It can be seen that the entire video has a pure black background, the left half is the source video (transparent video with Alpha channel) converted to pure black, and the right half is the non-transparent part of the source video converted to pure white;
In order to have a more direct understanding, we use Youku Video and Tencent Video as the standard, you can see:
HD | Ultra-clear | 1080P (Blu-ray) | |
Youku Video | Bit rate: >=800kbps Resolution: >=960x400 | Bit rate: >=1500kbps Resolution: >=1280x544 | Bit rate: >=3500kbps Resolution: >=1920x800 |
Tencent Video | Bit rate: >=800kbps Resolution: >=640×360 | Bit rate: >=1500kbps Resolution: >=960×540 | Bit rate: >=2500kbps Resolution: >=1920×1080 |
So choose the appropriate bit rate according to your actual situation; Click here to view Youku video upload standards; Click here to view Tencent video upload standards;
It should be noted that the width of the transparent video has actually doubled, but the final display will only show the transparent left part. In order to ensure the clarity of the transparent video, the user needs to make the left half of the resolution reach the desired standard Instead of looking at the resolution of the entire video.
Estimate the size of the video displayed in the scene in advance. As shown in the figure below, we have added a video animation of the lower limb rehabilitation robot to the WebAR scene, and then hope that the video animation will be displayed as 2/3 of the device screen width, then we can put the transparent video in the left half Part of the resolution is reduced to 2/3, for example: For example, there is an existing source video with Alpha channel, the resolution is 720x720, we only need its size to display 2/3 of the screen, then we can change the source video The resolution is first changed to 480x480, and the final transparent video resolution is 960x480;
The size of the video must be the same as the resolution of the video;
Generally speaking, if there is no special requirement, it is recommended to set the video frame rate to 25;
Please refer to the AR video conversion tutorial, click to jump
It should be noted that here we only explain how to convert a transparent video with an Alpha channel into a "transparent" video required by the Kivicube platform.
Import the video file to be made into AE, as shown in the figure:
Right-click in the blank area where the red letter is located in the picture below, and select New Position to create a new comp New comp settings: a) Customize the name; b) Set the width of the new comp at Width (the new width is twice the original video width, if the original video width is 1024, it should be set to 2048 here); c) After setting Click OK to confirm.
When the new comp is created, as shown in the figure:
Drag and drop the video material to the comp1 window, and rename it to "man3_1.mov" (rename method: right-click the newly dragged video name and select Rename);
At this time, you can see the content of the video material in the main window. Next, modify the position of the video material to align it with the left side of the main window. The modification method is: click the triangle symbol on the left side of the video material;
A drop-down menu will pop up at this time;
Adjust the position on the X axis later;
After the adjustment is completed, the video material "man3_1.mov" is aligned with the left side of the main window.
Use the same method to drag the video material to comp1 again (remember to name it "man3_2.mov"), and modify the position to align it with the right side of the main window, as shown in the figure:
When the position is aligned, we begin to realize the requirement that the left side of our video is colored and the right side is black and white. The method is: click the right mouse button in the comp1 window and select New—>Solid to create a solid layer. The aspect ratio at this time should be consistent with the aspect ratio of the video material.
When you click ok, as shown in the picture
Drag and drop the newly created solid layer between man3_1 and man3_2, and then click the box in the middle, as shown in the figure:
When the above content is completed, you can output a video (avi/mov) with a transparent channel. Video specification requirements are within the standard specifications given previously. As AE can't output .mp4 files natively, you need to convert the video to mp4 to use on the Kivicube platform, the conversion tutorial is as follows: https://www.yuque.com/kivicube/manual/ar-video#xdk2dz
