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Gain compression - Compression

A transistor's operating point may move with temperature, so higher power output may lead to compression due to collector dissipation. But it's not a change in gain; it's non-linear distortion. The output level stays relatively the same as the input level goes higher. Once the non-linear portion of the transfer characteristic of any amplifier is reached, any increase in input will not be matched by a proportional increase in output. Thus there is compression of gain. Also, at this time because the transfer function is no longer linear, harmonic distortion will result.

Gain compression - Compression

Compression of gain is caused by non-linear characteristics of the device when run at large amplitudes. With any signal, as the input level is increased beyond the linear range of the amplifier, gain compression will occur.

Color Cell Compression - Compression

The Color Cell Compression algorithm processes an image in eight steps, although one of the steps (step #6) is optional. It is assumed here that the input is a 24 bits/pixel image, as assumed in the original journal article, although other bit depths could be used.

Lossy compression - Compression ratio

The compression ratio (that is, the size of the compressed file compared to that of the uncompressed file) of lossy video codecs is nearly always far superior to that of the audio and still-image equivalents.

Compression stockings - Compression classes

Compression stockings are constructed using elastic fibers or rubber. These fibers help compress the limb, aiding in circulation.

Proof compression - Compression algorithms

Algorithms for compression of propositional resolution proofs include RecycleUnits, RecyclePivots, RecyclePivotsWithIntersection, LowerUnits, LowerUnivalents, Split, Reduce&Reconstruct, and Subsumption.

Compression stockings - Compression classes

Compression stockings are offered in different levels of compression. The unit of measure used to classify the pressure of the stockings is mmHg. They are often sold in a variety of pressure ranges. Over-the-counter support is available in 10-15 or 15-20 mmHg.

Gain compression - Intentional compression

In intentional compression (sometimes called automatic gain control or audio level compression) as used in devices called 'dynamic range compressors', the overall gain of the circuit is actively changed in response to the level of the input over time, so the transfer function remains linear over a short period of time. A sine wave into such a system will still look like a sine wave at the output, but the overall gain is varied, depending on the level of that sine wave. Above a certain input level, the output sine wave will always be the same amplitude. The output level of Intentional compression varies over time, in order to minimize non linear behavior. With gain compression, the opposite is true, its output is constant. In this respect intentional compression serves less of an artistic purpose.

One-way compression function - Compression

Some compression functions do not compress by half, but instead by some other factor. For example, input A might be 256 bits, and input B 128 bits, which are compressed to a single output of 128 bits. That is, a total of 384 input bits are compressed together to 128 output bits.

Schedule compression - Compression methods

The goal of schedule compression to shorten the project without amending the project scope, according to the schedule constraints, required time and other objectives. Any compression must be done in the critical path activities. The most common techniques used for schedule compression are:

Proof compression - Compression algorithms

Algorithms for compression of sequent calculus proofs include Cut-introduction and Cut-elimination.

One-way compression function - Compression

A compression function mixes two fixed length inputs and produces a single fixed length output of the same size as one of the inputs. This can also be seen as that the compression function transforms one large fixed-length input into a shorter, fixed-length output.

Cold compression therapy - Cold compression

Cold compression is a combination of cryotherapy and static compression commonly used for the treatment of pain and inflammation after acute injury or surgical procedures.

Dynamic range compression - Parallel compression

One technique is to insert the compressor in a parallel signal path. This is known as parallel compression, a form of upward compression that facilitates dynamic control without significant audible side effects, if the ratio is relatively low and the compressor's sound is relatively neutral. On the other hand, a high compression ratio with significant audible artifacts can be chosen in one of the two parallel signal paths—this is used by some concert mixers and recording engineers as an artistic effect called New York compression or Motown compression. Combining a linear signal with a compressor and then reducing the output gain of the compression chain results in low-level detail enhancement without any peak reduction (since the compressor significantly adds to the combined gain at low levels only). This is often beneficial when compressing transient content, since it maintains high-level dynamic liveliness, despite reducing the overall dynamic range.

Dynamic range compression - Serial compression

Serial compression is a technique used in sound recording and mixing. Serial compression is achieved by using two fairly different compressors in a signal chain. One compressor generally stabilizes the dynamic range while the other aggressively compresses stronger peaks. This is the normal internal signal routing in common combination devices marketed as compressor-limiters, where an RMS compressor (for general gain control) is followed by a fast peak sensing limiter (for overload protection). Done properly, even heavy serial compression can sound natural in a way not possible with a single compressor. It is most often used to even out erratic vocals and guitars.

Container compression test - Dynamic Compression

Containers can be subjected to compression forces that involve distribution dynamics. For example, a package may be impacted by an object being dropped onto it (vertical load) or impacted by freight sliding into it (horizontal load). Vehicle vibration can involve a stack of containers and create dynamic compression responses. Package testing methods are available to evaluate these compression dynamics.

Lossless compression - Lossless compression techniques

Lossless compression methods may be categorized according to the type of data they are designed to compress. While, in principle, any general-purpose lossless compression algorithm (general-purpose meaning that they can accept any bitstring) can be used on any type of data, many are unable to achieve significant compression on data that are not of the form for which they were designed to compress. Many of the lossless compression techniques used for text also work reasonably well for indexed images.

Compression ratio - Dynamic compression ratio

The two corrections for dynamic compression ratio affect cylinder pressure in opposite directions, but not in equal strength. An engine with high static compression ratio and late intake valve closure will have a dynamic compression ratio similar to an engine with lower compression but earlier intake valve closure.

Compression set - Compression Set A

This has the formal name compression set under constant force in air. In compression set A a force of 1.8 kN is applied to the specimen for a set time at a set temperature. Compression set A is defined as the percentage of original specimen thickness after the specimen has been left in normal conditions for 30 minutes. C A , the compression set A is given by C A = [(t o - t i ) / t o ] * 100 where t o is the original specimen thickness and t i is the specimen thickness after testing.

Lossless compression - Lossless compression methods

By operation of the pigeonhole principle, no lossless compression algorithm can efficiently compress all possible data. For this reason, many different algorithms exist that are designed either with a specific type of input data in mind or with specific assumptions about what kinds of redundancy the uncompressed data are likely to contain.