工作點滴 on Fran Kuo | R&D Leadership

[工作點滴] wireless module development newbie

Tue, 23 Apr 2013 00:00:00 +0000

I’ve started collecting the information around the end of 2010 because the wireless technology advanced to much higher bandwidth for multimedia streaming.
There are two conditions of the development that I thought.
1. To develop the whole wireless part by ourselves.
2. To buy the module directly from the supplier.
But some important factors that make me just ‘collect information’ at that moment.
For 1, the expense is very horrible.
- We have to pay chip vendor for NRE.
- We are new to be the player and we have no credit to the chip vendor.
- We have no equipment and we have to invest a lot to do it.
- There are lots of tasks need for the regulation.
To sum up, this is a money game for surveillance company and we see no market at that moment.
For 2, we could leverage a lot tasks to supplier but we still have to prepare equipment to verify the whole system and get the experience of the regulation. However, the module cost and performance ratio could not meet our requirement. It is quite challenge for me to persuade my boss to do it.
So what I can do is just keep attention on wireless technology.
Until now, I have the chance to do the development finally.
Although I’m newbie for wireless, it’s not too hard to enter this area. The reason is the technology become much mature and we can make it work even we do not know much about wireless. So, let’s just do it.
The module I use is based on Atheros AR6103 and AR6003. The driver of these two chips are similar.
The documents I study is are mainly from Atheros. I also reference the IEEE specification and search on Google.

[工作點滴] rtmps in rtmpdump with hardware engine development

Mon, 01 Apr 2013 00:00:00 +0000

Evostream server’s configuration for rtmps test

Add the following content in the acceptors part in config.lua.

This is for Win7 configuration and remember that we have to use double ‘' instead of single for path.

The cipherSuite parameter, we could reference http://www.openssl.org/docs/apps/ciphers.html#CIPHER_SUITE_NAMES

RTMP library

The library is main from rtmpdump. The webpage is http://rtmpdump.mplayerhq.hu.

The libssl library - SSLv23 method is used in the RTMPdump.

- SSLv23 method

A TLS/SSL connection established with these methods will understand the SSLv2, SSLv3, and TLSv1 protocol.

[工作點滴] message pack rpc install on openwrt

Mon, 04 Feb 2013 00:00:00 +0000

Message pack with RPC extension required 3 packages.

msgpack
msgpack-rpc
mpio

The msgpack and mpio are required by msgpack-rpc. The following are openwrt makefiles that I use to build the packages.

msgpack library

include $(TOPDIR)/rules.mk

PKG_NAME:=msgpack
PKG_VERSION:=0.5.7
PKG_RELEASE:=1

PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.gz
PKG_SOURCE_URL:=http://msgpack.org/releases/cpp/
PKG_MD5SUM:=705106a9378c792fe22d285dba5c142c
PKG_INSTALL:=1

include $(INCLUDE_DIR)/package.mk

define Package/msgpack
SECTION:=libs
CATEGORY:=Libraries
TITLE:=Message Pack library
URL:=http://msgpack.org
endef

define Package/msgpack/description
MessagePack is an efficient binary serialization format.
It lets you exchange data among multiple languages like JSON but it’s faster and smaller.
endef

[工作點滴] protocol buffer message

Thu, 31 Jan 2013 00:00:00 +0000

The statusapi.pb-c.h and statusapi.pb-c.c are generated. Only header file is printing here for further explaination.

statusap.pb-c.h

/* Generated by the protocol buffer compiler. DO NOT EDIT! */
#ifndef PROTOBUF_C_statusapi_2eproto__INCLUDED #define PROTOBUF_C_statusapi_2eproto__INCLUDED
#include <google/protobuf-c/protobuf-c.h>
PROTOBUF_C_BEGIN_DECLS

typedef struct _Statusapi__StatusRequestType Statusapi__StatusRequestType; typedef struct _Statusapi__StatusResponseType Statusapi__StatusResponseType; typedef struct _Statusapi__StatusParams Statusapi__StatusParams;

/* — enums — */

/* — messages — */
struct _Statusapi__StatusRequestType { ProtobufCMessage base; }; #define STATUSAPI__STATUS_REQUEST_TYPE__INIT \ { PROTOBUF_C_MESSAGE_INIT (&statusapi__status_request_type__descriptor) \ }

struct _Statusapi__StatusResponseType { ProtobufCMessage base; }; #define STATUSAPI__STATUS_RESPONSE_TYPE__INIT \ { PROTOBUF_C_MESSAGE_INIT (&statusapi__status_response_type__descriptor) \ }