Commit 239dab84 authored Apr 02, 2024 by guochuang

Matroskaextractor: improve findThumbnails() time.



For Matroska, traversing to find the first 20 keyframes is very
time-consuming, typically 1000 (1 key frame per 50 frames) - 2000 (
1 key frame per 100 frames) iterations are required, resulting in
findThumbnails() takes 2-4s, or even more.
Now add an additional judgment condition: when the parser time (the
timestamp of the current iteration block) exceeds 20s and at least one
key frame has been found, end the iteration.

Bug: 332463097
Test: atest CtsMediaExtractorTestCases
Change-Id: I21303552c4c862dd960054d86e1133e067f9326a
Signed-off-by: guochuang <guochuang@xiaomi.corp-partner.google.com>

parent 41829023

media/module/extractors/mkv/MatroskaExtractor.cpp

+7 −1

Original line number	Diff line number	Diff line
		@@ -2279,6 +2279,8 @@ void MatroskaExtractor::findThumbnails() {
		int64_t thumbnailTimeUs = 0;
		size_t maxBlockSize = 0;
		while (!iter.eos() && j < 20) {
		int64_t blockTimeUs = iter.blockTimeUs();

		if (iter.block()->IsKey()) {
		++j;

		@@ -2289,8 +2291,12 @@ void MatroskaExtractor::findThumbnails() {

		if (blockSize > maxBlockSize) {
		maxBlockSize = blockSize;
		thumbnailTimeUs = iter.blockTimeUs();
		thumbnailTimeUs = blockTimeUs;
		}
		}
		// Exit after 20s if we've already found at least one key frame.
		if (blockTimeUs > 20000000 && maxBlockSize > 0) {
		break;
		}
		iter.advance();
		}