1. Key difference 1: Syntax and Purpose: OpenCL is a language and framework that allows developers to write programs that run on heterogeneous platforms, including CPUs, GPUs, and other accelerators. It is primarily focused on parallel computing and data-parallel task execution. On the other hand, OpenCV is a library that provides a wide range of computer vision algorithms and functions. It is primarily used for image and video processing, machine learning, and computer vision applications.

2. Key difference 2: Execution Model: OpenCL follows a task-based execution model, where tasks are scheduled and executed in parallel on multiple devices. It provides explicit control over memory allocation and movement among devices. On the other hand, OpenCV is designed to be used in a sequential manner, where algorithms are executed one after another. It abstracts the underlying hardware and memory management, providing a high-level interface for developers.

3. Key difference 3: Language and API: OpenCL uses its own programming language based on C99, which allows developers to write low-level, optimized code for parallel processing. It provides an API for managing devices, executing tasks, and transferring data. On the other hand, OpenCV is primarily implemented in C++ and provides a C++ API for developers. It encapsulates complex algorithms and functions into easy-to-use interfaces, making it suitable for rapid prototyping and development.

4. Key difference 4: Scope of Functionality: OpenCL is a general-purpose computing framework and can be used for a wide range of applications beyond computer vision, such as scientific simulations, financial modeling, and data analytics. It provides low-level access to hardware resources and is highly customizable. On the other hand, OpenCV is specifically designed for computer vision tasks and provides a comprehensive set of algorithms and functions tailored for image and video processing.

5. Key difference 5: Portability and Compatibility: OpenCL is an open standard that is supported by a wide range of hardware vendors, including CPUs, GPUs, and FPGAs. It provides a platform-agnostic programming model, allowing developers to write code that can run on different devices. On the other hand, OpenCV is a library that can be used with various programming languages and platforms, including Windows, Linux, macOS, Android, and iOS. It provides a consistent interface across different platforms, making it easy to port applications.

6. Key difference 6: Performance Optimization: OpenCL provides low-level control over memory and task execution, allowing developers to optimize their code for performance. It supports features such as explicit memory movement, shared local memory, and fine-grained parallelism. On the other hand, OpenCV is optimized for ease of use and provides high-level interfaces that abstract the underlying hardware. It focuses on providing efficient implementations of commonly used computer vision algorithms, rather than fine-grained performance optimization.

In Summary, OpenCL is a language and framework for parallel computing on heterogeneous platforms, while OpenCV is a library for computer vision applications. OpenCL follows a task-based execution model with low-level control over memory and hardware, while OpenCV provides high-level interfaces and optimized implementations of computer vision algorithms. OpenCL is portable and widely supported by hardware vendors, while OpenCV is compatible with various platforms and programming languages.