Total Video2Gif is the best choice to convert movie clip to animated gif by freely setting start/end time, speed and size of clip. 

Supported input movie formats: 
WMV, MKV, AVI, DivX, XviD, MPEG, MP4, QT, RM, RMVB, M2T, FLV, MPEG, MPEG2 TS, ASF, 3GP, 3G2, GIF, H.264/MPEG-4 AVC, H.264/PSP AVC Video, MOV, FLV,iPod, PSP, Zune, Apple TV, iPhone, Nokia, Sony, BlackBerry, etc.

- Convert batch movie clips to animated gif files.

- Freely customize frame rate, frame size to change the speed, size of the clip.

- Set any time point you want as start and end time for the clip.

- Create infinite repeat gif just with a repeat switch.

- Apply different effects such as Rotation, Blur, Gray, Brightness, Contrast to movie clip.

- Preview movie clip before starting conversion.

Screenshots

Our products on App Store:

Total Video Converter Pro = Video/Audio Converter + DV Auto Importer + Video Combiner + GIF Exporter + Audio Extractor + Movie Effects + Video Multiplex

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Total Video Converter Lite - Absolutely Clean & Free - No Ads & Nothing to Pay!

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Audio Normalizer for Mac - Normalize all music and audio to the same volume level on Mac.

Batch Photo Editor - Image bulk processing app to add images and text watermarks to all your photos at a time.

Total Video2Gif - Convert movie clip to animated gif by freely setting start/end time, speed and size of clip.

Movie Effects - Add various video effects such as rotate, flip, contrast, brightness, smooth to your videos.

Intelligent Scissors - Remove Unwanted Object from Photo and Resize Image for Mac.

7Z-Rar - Convert between all video&audio on Mac