Cannot import Video. Unity Pro 5.3.3.

Hi!
Problem:
I cannot import Full HD video. Unity Pro 5.3.3.
Question
How can I import video? I wanna to save video quality.

My video info:

General

Complete name : F:\Video-Raw_SCADA_ m.mp4

Format : MPEG-4

Format profile : Base Media / Version 2

Codec ID : mp42

File size : 1.11 GiB

Duration : 5mn 0s

Overall bit rate : 31.8 Mbps

Encoded date : UTC 2016-03-15 17:57:09

Tagged date : UTC 2016-03-15 17:58:38

©TIM : 00:00:00:00

©TSC : 30000

©TSZ : 1001

Video

ID : 1

Format : AVC

Format/Info : Advanced Video Codec

Format profile : Main@L4.2

Format settings, CABAC : Yes

Format settings, ReFrames : 3 frames

Codec ID : avc1

Codec ID/Info : Advanced Video Coding

Duration : 5mn 0s

Bit rate mode : Variable

Bit rate : 31.6 Mbps

Maximum bit rate : 40.0 Mbps

Width : 1 920 pixels

Height : 1 080 pixels

Display aspect ratio : 16:9

Frame rate mode : Constant

Frame rate : 29.970 fps

Standard : NTSC

Color space : YUV

Chroma subsampling : 4:2:0

Bit depth : 8 bits

Scan type : Progressive

Bits/(Pixel*Frame) : 0.508

Stream size : 1.10 GiB (99%)

Language : English

Encoded date : UTC 2016-03-15 17:57:09

Tagged date : UTC 2016-03-15 17:57:09

Audio

ID : 2

Format : AAC

Format/Info : Advanced Audio Codec

Format profile : LC

Codec ID : 40

Duration : 5mn 0s

Bit rate mode : Variable

Bit rate : 192 Kbps

Maximum bit rate : 297 Kbps

Channel(s) : 2 channels

Channel positions : Front: L R

Sampling rate : 48.0 KHz

Compression mode : Lossy

Stream size : 6.78 MiB (1%)

Language : English

Encoded date : UTC 2016-03-15 17:57:09

Tagged date : UTC 2016-03-15 17:57:09

Looks like unity can not convert a video with the Advanced Video Codec.
Try to convert it to H264 codec or directly to ogg theora (the format unity will convert it to)

I’am trying to covert my video to ogg theora(.ogv file)
I have tried MiroConverter and MTS-Converter. This soft give me very bad quality of video.
Can you advice good simply video converter to ogv