基于DSP的低码率视频图像压缩与传输系统设计
摘要
目前,由于图像压缩技术和信号处理技术的发展,经过压缩处理的图像数据可大
大降低其数据容量和传输带宽,并可在一般的通信系统中进行传输了,例如现在的
会议电视、可视电话等。但这些系统设备复杂,价格昂贵,并且仍需较宽的频带,
在公用电话交换网(PSTN)和一般的话带无线电台中尚难使用。在 PSTN 网络相对比
较普及的今天,如何充分利用现有资源以满足人们进行视频监控与图像通信的需求,
是一个急待解决的课题。事实上,在很多实际使用场合并不一定需要活动图像传输,
能在秒的数量级内传输一幅一幅静止图像就可以了,本课题正是基于这一需求而提
出的,主要研究了低码率视频图像压缩与传输及其在 DSP 上实现的问题。
文章首先对系统的总体方案进行了设计,确定了以 C5416 作为主处理器,以 CMOS
图像传感器作为信源,并引入 CPLD 作为逻辑控制部分的硬件方案,文章接着对整个
系统的工作流程作了简要描述。
在接下来的章节里,分别就系统的三个功能模块——视频采集模块、JPEG 压缩
处理模块和图像数据传输模块,作了详细的分析与设计。视频采集模块采用的主要
芯片是 OV7620,文章对其性能和结构特点作了简单的介绍之后,重点分析了它通过
I2C 总线进行操作控制的方法,详细阐述了基于 CPLD 的帧存储器地址生成器的设计
过程;JPEG 压缩处理模块的设计是本文的另一重点,在介绍了 JPEG 算法的基本流程
和主要步骤之后,重点就该算法在 DSP 上的具体实现进行了论述;传输模块的基本
任务是将压缩的数据流通过调制解调器从电话线上发送出去,文章在对通信核心芯
片 TL16C750 作了详细介绍的基础上,给出了该模块的软硬件设计。
在本文最后,就整个系统的集成作了说明,并结合个人的设计体会给出了一些改
进的思路。
At present, with the development of image compressing technology and signal
processing technology, compressed image data can not only decrease the capacity of data
and bandwidths, but also can be transmitted through general channels, such as video TV,
video phone, etc., however, due to its complexity, high price and demand on more
bandwidths, it is difficult to be transmitted through public switch telephone net (PSTN).
Since PSTN has enjoyed great popularity nowadays, it is very urgent for us to make full
use of the resources to meet the keen demand of video surveillance and image
communication. In fact, active image transmission is not demanded on many situations in
our daily life, several frames per second of still image is enough to meet the demand.
Based on this demand, this paper deals with the issue of image coding and low rate
transferring based on digital signal processor (DSP).
First, the system scheme is stated at the beginning the paper, C5416 has been used as
main processor, CMOS image sensor as signal source and CPLD as logical controller.
Then, the paper gives a general description of the process of this system.
As follows, the paper gives details of the three main functional modules: video
capturing module, JPEG coding module and image transferring module. In the video
capturing module, after a brief introduction of the main integrated circuit (IC) OV7620,
the paper mainly analyzes the initializing and setting method of this IC and the address
generation process of the frame memory. In the JPEG coding module, after an expatiation
upon the basic flow and main steps of the JPEG algorithm, the paper puts an emphases on
its implementation based on DSP. In the image transferring module, the core IC
TL16C750 is illuminated and the hardware and software design is presented in details.
At the end of the paper, statements of the whole sytem integration and some ideas
about its improvement have been given.
大降低其数据容量和传输带宽,并可在一般的通信系统中进行传输了,例如现在的
会议电视、可视电话等。但这些系统设备复杂,价格昂贵,并且仍需较宽的频带,
在公用电话交换网(PSTN)和一般的话带无线电台中尚难使用。在 PSTN 网络相对比
较普及的今天,如何充分利用现有资源以满足人们进行视频监控与图像通信的需求,
是一个急待解决的课题。事实上,在很多实际使用场合并不一定需要活动图像传输,
能在秒的数量级内传输一幅一幅静止图像就可以了,本课题正是基于这一需求而提
出的,主要研究了低码率视频图像压缩与传输及其在 DSP 上实现的问题。
文章首先对系统的总体方案进行了设计,确定了以 C5416 作为主处理器,以 CMOS
图像传感器作为信源,并引入 CPLD 作为逻辑控制部分的硬件方案,文章接着对整个
系统的工作流程作了简要描述。
在接下来的章节里,分别就系统的三个功能模块——视频采集模块、JPEG 压缩
处理模块和图像数据传输模块,作了详细的分析与设计。视频采集模块采用的主要
芯片是 OV7620,文章对其性能和结构特点作了简单的介绍之后,重点分析了它通过
I2C 总线进行操作控制的方法,详细阐述了基于 CPLD 的帧存储器地址生成器的设计
过程;JPEG 压缩处理模块的设计是本文的另一重点,在介绍了 JPEG 算法的基本流程
和主要步骤之后,重点就该算法在 DSP 上的具体实现进行了论述;传输模块的基本
任务是将压缩的数据流通过调制解调器从电话线上发送出去,文章在对通信核心芯
片 TL16C750 作了详细介绍的基础上,给出了该模块的软硬件设计。
在本文最后,就整个系统的集成作了说明,并结合个人的设计体会给出了一些改
进的思路。
At present, with the development of image compressing technology and signal
processing technology, compressed image data can not only decrease the capacity of data
and bandwidths, but also can be transmitted through general channels, such as video TV,
video phone, etc., however, due to its complexity, high price and demand on more
bandwidths, it is difficult to be transmitted through public switch telephone net (PSTN).
Since PSTN has enjoyed great popularity nowadays, it is very urgent for us to make full
use of the resources to meet the keen demand of video surveillance and image
communication. In fact, active image transmission is not demanded on many situations in
our daily life, several frames per second of still image is enough to meet the demand.
Based on this demand, this paper deals with the issue of image coding and low rate
transferring based on digital signal processor (DSP).
First, the system scheme is stated at the beginning the paper, C5416 has been used as
main processor, CMOS image sensor as signal source and CPLD as logical controller.
Then, the paper gives a general description of the process of this system.
As follows, the paper gives details of the three main functional modules: video
capturing module, JPEG coding module and image transferring module. In the video
capturing module, after a brief introduction of the main integrated circuit (IC) OV7620,
the paper mainly analyzes the initializing and setting method of this IC and the address
generation process of the frame memory. In the JPEG coding module, after an expatiation
upon the basic flow and main steps of the JPEG algorithm, the paper puts an emphases on
its implementation based on DSP. In the image transferring module, the core IC
TL16C750 is illuminated and the hardware and software design is presented in details.
At the end of the paper, statements of the whole sytem integration and some ideas
about its improvement have been given.
引文
[1] 黎洪松.数字视频技术及其应用.北京:清华大学出版社,1997
[2] 张雄伟,陈亮,徐光辉.DSP 芯片的原理与开发应用(第2版).北京:电子工业
出版社,2003
[3] 秦石乔,王省书,何焰兰等.CMOS 数字摄象 IC 及其在视频图像采集中的应用.计
算机工程,1999,25(5):55~56
[4] 聂飞,冯宗哲,郭宝龙等.嵌入式视频采集系统的实现方法研究.电视技术,2003,
8:46~49
[5] 汪安民.TMS320C54xx DSP 实用技术.北京:清华大学出版社,2002
[6] TMS320VC5416 Fixed-Point Digital Signal Processor.Texas Instruments Incorpora-
ted, Literature Number: SPRS095K, 2003
[7] Wissam Rabadi, Raj Talluri, Klaus Illgner et al. Programmable DSP Platform for
Digital Still Cameras.Texas Instruments Incorporated, Literature Number:
SPRA651-April, 2000
[8] 余国华,冯启明.基于 CMOS 图像传感器的视频采集系统设计.武汉理工大学学
报,2004,28(1):145~147
[9] 段传华,陈广旭,王明俊.基于定点 DSP 的 CMOS 数字视频监控终端设计.单片
机及嵌入式系统应用,2003,6:49~51
[10] 刘智辉.基于 TMS320C542 的彩色图像采集、压缩与水声传输系统的研究:[学位
论文].厦门:厦门大学,2000
[11] TMS320C54x Evaluation Module Technical Reference .Texas Instruments
Incorporated,Literature Number:SPRU135,1995
[12] 谢庆胜.图像采集与传输系统——数字化监控系统的设计与实现:[学位论文].西
安:西安交通大学,2001
51
[13] 王侃伟,方宗德.嵌入式指纹识别系统开发.电子技术应用,2003,4:17~19
[14] 杨志龙,张维新,寇建锋.基于 TMS320VC5402 的指纹识别系统. 单片机及嵌入式
系统应用,2003,3:53~56
[15] 吴朝晖,郑学仁,胡鹏.嵌入式微处理器接口总线控制器的 CPLD 设计.半导体技
术,2001,26(4):46~49
[16] 龚静康,何菲玲.CPLD 在 DSP 处理模板中的应用.声学与电子工程,2003,3:
25~28
[17] IS61LV5128AL 512K x 8 High Seed CMOS Static RAM. Integrated Silicon Solution,
Inc., 2003
[18] Am29LV200B 2 Megabit (256 K x 8-Bit/128 K x 16-Bit) CMOS 3.0 Volt-only Boot
Sector Flash Memory. Advanced Micro Devices, Inc., 2002
[19] OV7620 Single-chip CMOS VGA Color Digital Camera. OmniVision Inc., 2000
[20] Interfacing the ADSP-21535 to Single-chip CIF Digital Camera OV6630 over the
External Memory Bus.Analog Devices, Inc., 2003
[21] 何立民. I2C 总线应用系统设计.北京:北京航空航天大学出版社,2002
[22] 刘滨,姜广欣,杨占录. I2C 串行总线技术在 DSP 系统中的虚拟实现.微计算机
信息,2003,45(6):12~13
[23] 吴开杰,邵蔚,李刚.TMS320VC5410 的 McBSP 串行接口技术与程序设计.单片
机与嵌入式系统应用,2001,11:34~38
[24] 黄正瑾,徐坚,章小丽等.CPLD 系统设计技术入门与应用.北京:电子工业出版
社,2002
[25] 卢毅,赖杰.VHDL 与数字电路设计.北京:科学出版社,2001
[26] 曾洪庆.基于 DDD-T 的高效图像压缩编码系统研究与设计:[学位论文].北京:北
京大学,2000
[27] G.K.Wallace.The JPEG still picture compression standard. Communications
of ACM, 1991,4:30~44
[28] ISO/IEC 10918-1:Information technology—Digital compression and coding of
continuous-tone still images:Requierments and guidelines. ISO/IEC, 1994
52
[29] C. Loeffler, A. Ligtenberg and G. Moschytz.Practical Fast 1-D DCT Algorithms with
11 Multiplications. Proc. Int'l. Conf. on Acoustics, Speech, and Signal Processing
1989 (ICASSP 89) :988-991
[30] TMS320C54x DSP CPU Reference Guide. Texas Instruments Incorporated,
Literature Number: SPRU131G,2001
[31] TMS320C54x DSP Reference Set Volume 4: Applications Guide. Texas Instruments
Incorporated, Literature Number: SPRU173, 1996
[32] 方芳,张太镒,孙建成.TMS320C54x 系列 DSP 存储空间的配置.电子产品世界,
2003,1:67~68
[33] 王永军,丛玉珍.数字逻辑与数字系统.北京:电子工业出版社,1997
[34] TMS320C54x Assembly Language Tools User’s Guide. Texas Instruments
Incorporated, Literature Number: SPRU102F, 2002
[35] 周霖.DSP 通信工程技术应用.北京:国防工业出版社,2004
[36] 李鹏.计算机通信技术及其程序设计.西安:西安电子科技大学出版社,1998
[37] TL16C750 Asynchronous Communications Element With 64-byte FIFOs and
Autoflow Control.Texas Instruments Incorporated, Literature Number: SPRA651,
April, 1997
[38] 邓 勇,施文康.利用 TL16C750 实现 DSP 与 PC 机的高速串口通信.国外电子元
器件,2000,9:28~31
[39] 李现勇.Visual C++串口通信技术与工程实践.北京:人民邮电出版社,2002
[40] 精英科技.电路板设计完全手册.北京:中国电力出版社,2002
[41] 迟泽英,李坤宇,李武森等.高速 DSP 视频图像数字处理电路几个关键问题的研究
分析. 红外技术,2001,23(2):24~27
[42] 清源科技.TMS320C54x DSP 硬件开发教程.北京:机械工业出版社,2003
[2] 张雄伟,陈亮,徐光辉.DSP 芯片的原理与开发应用(第2版).北京:电子工业
出版社,2003
[3] 秦石乔,王省书,何焰兰等.CMOS 数字摄象 IC 及其在视频图像采集中的应用.计
算机工程,1999,25(5):55~56
[4] 聂飞,冯宗哲,郭宝龙等.嵌入式视频采集系统的实现方法研究.电视技术,2003,
8:46~49
[5] 汪安民.TMS320C54xx DSP 实用技术.北京:清华大学出版社,2002
[6] TMS320VC5416 Fixed-Point Digital Signal Processor.Texas Instruments Incorpora-
ted, Literature Number: SPRS095K, 2003
[7] Wissam Rabadi, Raj Talluri, Klaus Illgner et al. Programmable DSP Platform for
Digital Still Cameras.Texas Instruments Incorporated, Literature Number:
SPRA651-April, 2000
[8] 余国华,冯启明.基于 CMOS 图像传感器的视频采集系统设计.武汉理工大学学
报,2004,28(1):145~147
[9] 段传华,陈广旭,王明俊.基于定点 DSP 的 CMOS 数字视频监控终端设计.单片
机及嵌入式系统应用,2003,6:49~51
[10] 刘智辉.基于 TMS320C542 的彩色图像采集、压缩与水声传输系统的研究:[学位
论文].厦门:厦门大学,2000
[11] TMS320C54x Evaluation Module Technical Reference .Texas Instruments
Incorporated,Literature Number:SPRU135,1995
[12] 谢庆胜.图像采集与传输系统——数字化监控系统的设计与实现:[学位论文].西
安:西安交通大学,2001
51
[13] 王侃伟,方宗德.嵌入式指纹识别系统开发.电子技术应用,2003,4:17~19
[14] 杨志龙,张维新,寇建锋.基于 TMS320VC5402 的指纹识别系统. 单片机及嵌入式
系统应用,2003,3:53~56
[15] 吴朝晖,郑学仁,胡鹏.嵌入式微处理器接口总线控制器的 CPLD 设计.半导体技
术,2001,26(4):46~49
[16] 龚静康,何菲玲.CPLD 在 DSP 处理模板中的应用.声学与电子工程,2003,3:
25~28
[17] IS61LV5128AL 512K x 8 High Seed CMOS Static RAM. Integrated Silicon Solution,
Inc., 2003
[18] Am29LV200B 2 Megabit (256 K x 8-Bit/128 K x 16-Bit) CMOS 3.0 Volt-only Boot
Sector Flash Memory. Advanced Micro Devices, Inc., 2002
[19] OV7620 Single-chip CMOS VGA Color Digital Camera. OmniVision Inc., 2000
[20] Interfacing the ADSP-21535 to Single-chip CIF Digital Camera OV6630 over the
External Memory Bus.Analog Devices, Inc., 2003
[21] 何立民. I2C 总线应用系统设计.北京:北京航空航天大学出版社,2002
[22] 刘滨,姜广欣,杨占录. I2C 串行总线技术在 DSP 系统中的虚拟实现.微计算机
信息,2003,45(6):12~13
[23] 吴开杰,邵蔚,李刚.TMS320VC5410 的 McBSP 串行接口技术与程序设计.单片
机与嵌入式系统应用,2001,11:34~38
[24] 黄正瑾,徐坚,章小丽等.CPLD 系统设计技术入门与应用.北京:电子工业出版
社,2002
[25] 卢毅,赖杰.VHDL 与数字电路设计.北京:科学出版社,2001
[26] 曾洪庆.基于 DDD-T 的高效图像压缩编码系统研究与设计:[学位论文].北京:北
京大学,2000
[27] G.K.Wallace.The JPEG still picture compression standard. Communications
of ACM, 1991,4:30~44
[28] ISO/IEC 10918-1:Information technology—Digital compression and coding of
continuous-tone still images:Requierments and guidelines. ISO/IEC, 1994
52
[29] C. Loeffler, A. Ligtenberg and G. Moschytz.Practical Fast 1-D DCT Algorithms with
11 Multiplications. Proc. Int'l. Conf. on Acoustics, Speech, and Signal Processing
1989 (ICASSP 89) :988-991
[30] TMS320C54x DSP CPU Reference Guide. Texas Instruments Incorporated,
Literature Number: SPRU131G,2001
[31] TMS320C54x DSP Reference Set Volume 4: Applications Guide. Texas Instruments
Incorporated, Literature Number: SPRU173, 1996
[32] 方芳,张太镒,孙建成.TMS320C54x 系列 DSP 存储空间的配置.电子产品世界,
2003,1:67~68
[33] 王永军,丛玉珍.数字逻辑与数字系统.北京:电子工业出版社,1997
[34] TMS320C54x Assembly Language Tools User’s Guide. Texas Instruments
Incorporated, Literature Number: SPRU102F, 2002
[35] 周霖.DSP 通信工程技术应用.北京:国防工业出版社,2004
[36] 李鹏.计算机通信技术及其程序设计.西安:西安电子科技大学出版社,1998
[37] TL16C750 Asynchronous Communications Element With 64-byte FIFOs and
Autoflow Control.Texas Instruments Incorporated, Literature Number: SPRA651,
April, 1997
[38] 邓 勇,施文康.利用 TL16C750 实现 DSP 与 PC 机的高速串口通信.国外电子元
器件,2000,9:28~31
[39] 李现勇.Visual C++串口通信技术与工程实践.北京:人民邮电出版社,2002
[40] 精英科技.电路板设计完全手册.北京:中国电力出版社,2002
[41] 迟泽英,李坤宇,李武森等.高速 DSP 视频图像数字处理电路几个关键问题的研究
分析. 红外技术,2001,23(2):24~27
[42] 清源科技.TMS320C54x DSP 硬件开发教程.北京:机械工业出版社,2003