video

Project and build structure for Microsoft DirectShow based virtual webcam application on Window 10

橙三吉。 提交于 2021-02-10 18:23:03
问题 I am trying to create simplest virtual webcam application which can display image file on my local filesystem. After initial research on stackoverflow links and seeing OBS Studio source code I got some idea how can I achieve this. I would need to use Microsoft DirectShow. I would need to develop one source filter that would work as capture filter using IBaseFilter I would need to develop another source filter that would work as output filter or virtual webcam filter. I would need to compile

Ffmpeg concat demuxer shifts video stream start time

[亡魂溺海] 提交于 2021-02-10 17:53:03
问题 Summary Ffmpeg concat demuxer shifts video stream start time when invoked with -c copy option. Reproduction Given an before.mp4 containing video and audio streams both with start_time=0 and start_pts=0 . Given concat demuxer input file concat.txt with contents: file before.mp4 Run command ffmpeg -f concat -i concat.txt -c copy concat.mp4 Run command ffprobe concat.mp4 -show_streams and observe that video stream start_time and start_pts are now non-zero (in my tests, the magnitude of this

is there a way to record videos in kivy?

别说谁变了你拦得住时间么 提交于 2021-02-10 14:10:42
问题 I am displaying the camera video in Kivy, but I can't find a way to record the video, I tried to use OpenCV Videowriter but because of the updating ( Clock.schedule_interval(self.update, 1.0/33.0)) it is constantly overwriting so the video that it saved is one image, does anybody have an alternative way. 回答1: Please look into the below code which may serve your purpose. The main code is taken from the link: https://www.codingforentrepreneurs.com/blog/how-to-record-video-in-opencv-python. I

is there a way to record videos in kivy?

杀马特。学长 韩版系。学妹 提交于 2021-02-10 14:07:33
问题 I am displaying the camera video in Kivy, but I can't find a way to record the video, I tried to use OpenCV Videowriter but because of the updating ( Clock.schedule_interval(self.update, 1.0/33.0)) it is constantly overwriting so the video that it saved is one image, does anybody have an alternative way. 回答1: Please look into the below code which may serve your purpose. The main code is taken from the link: https://www.codingforentrepreneurs.com/blog/how-to-record-video-in-opencv-python. I

How do I use the FPS argument in cv2.VideoWriter?

自作多情 提交于 2021-02-10 12:12:38
问题 Ok, so I am making a video. I want to know exactly how to use the FPS argument. It is a float, so I assumed it was what interval do I want between each frame. Can you give an example? I just want to know how the video would change with varying FPS argument values., because my video I made is way too fast now. Thanks! 回答1: It really is just that - frames per second . In other words, how many frames do you want to display every second? Here is an example: writer = cv2.VideoWriter(filename="my

Can't set the output type on an HEVC decoder IMFTransform

微笑、不失礼 提交于 2021-02-10 05:30:50
问题 I've written this program to setup an HEVC decoder based on https://docs.microsoft.com/en-us/windows/win32/medfound/supporting-direct3d-11-video-decoding-in-media-foundation. Everything works fine until the end when I call result = decoder->SetOutputType(0, media_type, 0); this returns the error MF_E_ATTRIBUTENOTFOUND . I'm not sure what's wrong, this error isn't described in the SetOutputType documentation and I've only found a couple examples of HEVC decoding with MF and none of them

In ffmpeg, how do I scale dvdsub subtitles to match video size, using scale2ref filter?

旧时模样 提交于 2021-02-10 04:26:38
问题 I have an mpeg file, recorded from live TV, containing video and multiple audio and subtitles streams. My eventual goal is to be able to create a smaller video file as the mpeg file is multi-gigabytes in size. My first step on that path is just to be able to select one each of the video, audio and subtitle streams and copy them to an mkv file, discarding the streams I'm not interested in. (I chose mkv as it will allow storing a dvdsub subtitle stream where other container formats wont.) The

In ffmpeg, how do I scale dvdsub subtitles to match video size, using scale2ref filter?

给你一囗甜甜゛ 提交于 2021-02-10 04:23:12
问题 I have an mpeg file, recorded from live TV, containing video and multiple audio and subtitles streams. My eventual goal is to be able to create a smaller video file as the mpeg file is multi-gigabytes in size. My first step on that path is just to be able to select one each of the video, audio and subtitle streams and copy them to an mkv file, discarding the streams I'm not interested in. (I chose mkv as it will allow storing a dvdsub subtitle stream where other container formats wont.) The

In ffmpeg, how do I scale dvdsub subtitles to match video size, using scale2ref filter?

为君一笑 提交于 2021-02-10 04:17:29
问题 I have an mpeg file, recorded from live TV, containing video and multiple audio and subtitles streams. My eventual goal is to be able to create a smaller video file as the mpeg file is multi-gigabytes in size. My first step on that path is just to be able to select one each of the video, audio and subtitle streams and copy them to an mkv file, discarding the streams I'm not interested in. (I chose mkv as it will allow storing a dvdsub subtitle stream where other container formats wont.) The

In ffmpeg, how do I scale dvdsub subtitles to match video size, using scale2ref filter?

旧城冷巷雨未停 提交于 2021-02-10 04:17:26
问题 I have an mpeg file, recorded from live TV, containing video and multiple audio and subtitles streams. My eventual goal is to be able to create a smaller video file as the mpeg file is multi-gigabytes in size. My first step on that path is just to be able to select one each of the video, audio and subtitle streams and copy them to an mkv file, discarding the streams I'm not interested in. (I chose mkv as it will allow storing a dvdsub subtitle stream where other container formats wont.) The