Best Video Editing Software to edit m4v,mpg,mkv,flv videos with zero quality lossing

How do I rotate my videos ?
"I took a video clip when the camera was held vertically, and when downloaded it to my mac, it was 90 degrees flipped."
Have you also have this same matter? and how to flip your videos upside down,vertically or horizontally on Windows? Following three method to rotate/flip videos on Win.
1. Rotate or flip videos or photos in Window Movie Maker
First, please convert your recorded HD file format like MTS,M2TS,TS etc to a format readable by Windows Movie Maker software (e.g .avi, .wmv, .mpg, .mpeg etc video file format). Then import the video clip into Windows Movie Maker, drag the imported video clip and drop it onto the timeline, on the Tools menu, click Video Effects. To rotate the video clip to the right, drag the Rotate 90 video effect and drop it onto the movie on the timeline. To rotate the video clip to the left, drag the Rotate 270 video effect and drop it onto the movie on the timeline. Last, please find File menu, click Save Movie File. Unfortunately, Windows Movie Maker can't import MKV video format. So you could rotate MKV with WMM.

2. Rotate or flip videos or photos using iOrgsoft Video Editor
If you want to convert the video to any other formats like MKV, WMV, AVI, MOV, MP4, VOB, MPEG, H.264, etc , at the same time like to edit the clips by rotating, cropping, trimming, Effect, adding logo, etc, please don't hesitate to download MKV Editor now, self-explanatory interface, easy-to-control. Then launch it, import video files, click Edit, click Flip button in the new interface to rotate the videos and get correct one. You could see the effect in the right preview screen. When the video clip is oriented correctly, click the OK, select output format, and click Convert to export your videos.

With this smart video flipper, you can rotate video 90 degrees or by any degrees until normal upright position is achieved.
Key functions of iOrgsoft Video Editor:
Fine-tune options to enhance your video in clicks.
Edit video/audio/photos with go-to features like trim, split, crop, etc.
Make a picture-in-picture video.
Control the action with speed up and slow down effects.
Change the voice for fun.
Add animated titles with an array of text effects.
Share your video anywhere: TV, YouTube, Facebook, iPhone, PSP, etc.
If you have download mpg,m4v,flv etc video format, you can also use M4V Editor , MPG Editor to help you merge,clip,crop,trim video. You can also merge videos with easy-to-use video merger .
If you are mac user, you can also try to use iOrgsoft Video Editor for Mac. As a video cutter/trimmer/splitter/joiner, iOrgSoft Video Editor for Mac has so many brilliant editing features to edit and create videos in a large variety of file types with ease for Mac users, besides, Mac video editor can be severed as a video converter which can convert among popular video formats.
FLV is a popular flash video and almost every video sharing site uses FLV to stream videos online. If you want to edit flv mac , you can try to use FLV Editor Mac to help you easy edit flv video with high quality.