A remote weather station transmits two data streams to a central server:
Which statement correctly identifies the most appropriate compression method for each stream, along with the correct technical justification?
Stream 1: Run-Length Encoding (a lossy technique), because sequential identical readings can be permanently discarded. Stream 2: Huffman coding (a lossy technique), because frequent pixel values are mapped to shorter binary codes.
Stream 1: Lossless compression, because precise numerical readings must be reconstructed bit-for-bit to prevent scientific errors. Stream 2: Lossy compression, because minor visual artifacts in the cloud monitor are acceptable, and lossy compression achieves much higher compression ratios.
Stream 1: Lossy compression, because numerical readings contain high-frequency noise that can be discarded without affecting scientific validity. Stream 2: Lossless compression, because video frames require absolute pixel-level fidelity to prevent metadata corruption.
Stream 1: Lossless compression, because it permanently deletes redundant bits, eliminating the need for a decompression stage. Stream 2: Lossy compression, because it utilizes error-detection codes to perfectly restore any discarded image data upon receipt.
37 exam-style questions on AQA GCSE Computer Science Data compression. Each one has a worked solution and a mark scheme showing where the marks go.