In this paper, we study and analyze the computational complexity of a software-based H.264/AVC baseline profile decoder. Our analysis is based on determining the number of basic computational operations required by a decoder to perform the key decoding subfunctions. The frequency of use of each of the required decoding subfunctions is empirically derived using bitstreams generated from two different encoders for a variety of content, resolutions and bit rates. Using the measured frequencies, estimates of the decoder time complexity for various hardware platforms can be determined. A detailed example is provided to assist readers in deriving their own time complexity estimates. We compare the resulting estimates to numbers measured for an optimized decoder on the Pentium 3 hardware platform. We then use those numbers to evaluate the dependence of the time complexity of each of the major decoder subfunctions on encoder characteristics, content, resolution and bit rate. Finally, we compare an H.264/AVC-compliant baseline decoder to a decoder that is compliant with the H.263 standard, which is currently dominant in interactive video applications. Both "C" only decoder implementations were compared on a Pentium 3 hardware platform. Our results indicate that an H.264/AVC baseline decoder is approximately 2.5 times more time complex than an H.263 baseline decoder.

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Blood flow and shunt quantification measured at multiple levels and performed by different readers are reproducible and consistent with 4D flow MRI.

In this review of the literature the goal was to determine the frequency and relevance of hemodynamic instability after carotid artery (CA) angioplasty and stent placement. Hemodynamic instability after CA angioplasty and stent placement is a well-recognized phenomenon that occurs in 29 to 51% of patients undergoing the procedure. In some patients this problem is severe enough to warrant treatment with vasopressor agents. Features observed on clinical and angiographic evaluation can help clinicians identify patients who are at risk. Hemodynamic fluctuations encountered as a result of CA angioplasty and stent placement may have adverse clinical consequences, including a higher incidence of myocardial infarction and stroke. Proposed measures to prevent this complication include prophylactic placement of transvenous pacemakers or pretreatment with atropine. Unfortunately, no randomized trials are currently available to assess the efficacy of these approaches. Hemodynamic instability is a common finding after CA angioplasty and stent placement. Clinicians can predict which patients are at risk by considering angiographic and clinical features.

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The publication of this Accepted Manuscript is provided to give early visibility to the contents of the article, which will undergo additional copyediting, typesetting, and review before it is published in its final form. During the production process, errors may be discovered that could affect the content of the Accepted Manuscript. All legal disclaimers that apply to the journal pertain. The reader is cautioned to consult the definitive version of record before relying on the contents of this document.