구차니의 잡동사니 모음

ppt 에 추가된 내용으로

부팅 시간이

linux 2.6.7 - 437.11

uclinux 2.6.7 - 415.16

으로 22초 정도 단축된다.

context switching 에 소요되는 시간인

linux - avg 110us

uclinux - avg 20us

에 비하면... 의외로 미미한 수준?

MMU 지원을 받지 못해 소스를 수정해야 하는 오버헤드를 생각하면

그리 큰 성능향상이라고 하긴 그럴 듯..

[링크 : http://bit.sparcs.org/~gangster/publication/uc_linux_fall.ppt]

[링크 : http://opensrc.sec.samsung.com/document/uc-linux-04_sait.pdf]

[링크 : http://micrium.com/rtos/ucosii/overview/]

[링크 : https://www.csie.ntu.edu.tw/~d6526009/ucOS2/Chapter-1.pdf]

+

[링크 : http://repilria.tistory.com/382]

What is uClinux?

The original uClinux was a derivative of Linux 2.0 kernel intended for microcontrollers without Memory Management Units (MMUs). However, the Linux/Microcontroller Project has grown both in brand recognition and coverage of processor architectures. Today's uClinux as an operating system includes Linux kernel releases for 2.0 2.4 and 2.6 as well as a collection of user applications, libraries and tool chains.

[링크 : http://www.uclinux.org/description/]

[링크 : http://www.uclinux.org/]

[링크 : http://www.uclinux.org/pub/uClinux/]

[링크 : http://sourceforge.net/projects/uclinux/]

[링크 : https://wiki.kldp.org/wiki.php/WhyIsMallocDifferentUnderUclinux]

[링크 : http://goo.gl/pzUmg] atmega1284p uclinux

+

[링크 : https://wiki.kldp.org/wiki.php/%B8%AE%B4%AA%BD%BA%C4%BF%B3%CE#s-5]

FreeRTOS is designed to be small and simple. The kernel itself consists of only three or four C files. To make the code readable, easy to port, and maintainable, it is written mostly in C, but there are a few assembly functions included where needed (mostly in architecture-specific scheduler routines).

Supported architectures

ARM architecture

 ARM7

 ARM9

 ARM Cortex-M0

 ARM Cortex-M0+

 ARM Cortex-M3

 ARM Cortex-M4

 ARM Cortex-A

Atmel

 Atmel AVR

 AVR32

 SAM3

 SAM4

 SAM7

 SAM9

 SAM D20

 SAM L21

Intel

 x86

 8052

[링크 : https://en.wikipedia.org/wiki/FreeRTOS]

[링크 : http://www.freertos.org/]

[링크 : http://sourceforge.net/projects/freertos/]

Linux support

The mainline Linux kernel gained support for OpenRISC in version 3.1.[17] The implementation merged in this release is the 32-bit OpenRISC 1000 family (or1k).[18] Previously OpenRISC 1000 architecture, but this has now been superseded by the mainline port.

RTOS support

A number of real-time operating systems have been ported to OpenRISC, including RTEMS, FreeRTOS and eCos.

QEMU support

Since version 1.2 [19] QEMU supports emulating OpenRISC platforms.

[링크 : https://en.wikipedia.org/wiki/OpenRISC]

[링크 : http://openrisc.io/]

그러니까.. AVB가 인프라고

RAW video는 기존의 표준이 있으니 RTP에 하나 추가해서

RAW 데이터를 전송하면 끝?

AVB - Audio video Bridge

[링크 : http://www.tta.or.kr/data/weekly_view.jsp?news_id=1926]

[링크 : https://en.wikipedia.org/wiki/Audio_Video_Bridging]

uncompressed video over IP

[링크 : http://www.tvtechnology.com/miscellaneous/0008/uncompressed-video-over-ip/206200]

RTP AVP(Audio Video Profile)

[링크 : https://en.wikipedia.org/wiki/RTP_audio_video_profile]

RTP Payload Format for Uncompressed Video

[링크 : https://tools.ietf.org/html/rfc4175]

[링크 : https://itea3.org/.../09039-MEDIATE-WP-2-MediateD221StandardsandInteroperabilityv11pdf.pdf]

[링크 : https://csperkins.org/research/ultragrid/2004-07-APAN.pdf]

[링크 : http://www.apan.net/meetings/tokyo2006/presentation/2006-01-APAN-STDs.pdf]

[링크 : https://en.wikipedia.org/wiki/Real-time_Transport_Protocol]

[링크 : https://en.wikipedia.org/wiki/Real_Time_Streaming_Protocol]

RTSP = RTCP + RTP

[링크 : http://nenunena.tistory.com/94]

네이밍 센스가... 다른건가

[링크 : http://www.ktncusa.com/_media/EZHD-CameraChart_vs1.2.pdf]

[링크 : https://www.youtube.com/watch?v=3SGll7OdHdI]

SDI

3G-SDI

이런게 나와서 먼가해서 찾아 봤더니 -_-

Gbps 의 G

즉, 12G SDI는 12Gbps를 전송할 수 있는 녀석

[링크 : http://en.wikipedia.org/wiki/Serial_digital_interface]

HDCVI was developed by Dahua and is being licensed to other manufacturers both directly and via the HDcctv Alliance as HDcctv 2.0 AT.

HD-TVI was developed by Techpoint, a U.S. semiconductor manufacturer. It has been licensed to Dahua's largest competitor, Hikvision, among others.

AHD is developed by Korean Nextxhip for beating CVI and TVI

[링크 : http://www.cctvforum.com/viewtopic.php?f=5&t=42549]

High Definition Composite Video Interface

High Definition Transport Video Interface

Analogue High Definition

[링크 : https://www.linkedin.com/pulse/20140912094320-252393278-let-s-talk-about-cvi-tvi-ahd]

HDCVI ( High Definition Composite Video Interface) is a solution for megapixel high definition applications, featuring non-latent long-distance transmission at a lower cost. The name has to do with its baseband and quadrature amplitude modulation technology, which is able to avoid CVBS cross talk, completely separate brightness and hue signal, and further enhances video quality.

[링크 : http://camstarusa.com/2014/12/hd-cvi-hd-tvi-technologies/]

Better Anti-Interference Capability:

The anti-interference capability of HD-SDI solution is relatively poor when been placed against high-frequent radiation environment, which could lead to higher bit error ratio while the HDCVI adopts low-frequency modulation technology, making it free from the high-frequency wireless electric radiation to ensure stable video transmission at high image quality.

[링크 : http://arindamcctvaccesscontrol.blogspot.kr/search/label/HDTVI]

음.. 외국꺼라 피트인가?

아무튼 500m 정도 전송가능한 규격으로

HD-SDI가 150m 정도가 리피터 없이 보낼수 있는 한계치 이기에 거리로 인한 메리츠가 존재하는 듯

(어쩌면 거리가 전부일지도)

[링크 : http://www.supercircuits.com/lp/compare-hd-analog-video-formats]

[링크 : http://www.hisharp.com/TVI/tvi_en.pdf] HD-TVI

[링크 : http://www.dahuasecurity.com/hdcvi/hdcvi-intro.html] HD-CVI

+ 2015.05.08

EX-SDI eyenix

[링크 : http://www.eyenix.com/index/sub01.php?vmenu=v0201]

+

2015.06.01

VLC - Visually Lossless Codec

[링크 : http://www.securityworldmag.co.kr/news/news_view.asp?idx=2893&part_code=01]