C++ KeyedVector::clear方法代码示例

//.........这里部分代码省略.........
        int64_t duration;
        CHECK(format->findInt64("durationUs", &duration));

        // Since we got the duration now, correct the start time.
        if (enableTrim) {
            if (trimStartTimeUs > duration) {
                fprintf(stderr, "Warning: trimStartTimeUs > duration,"
                                " reset to 0\n");
                trimStartTimeUs = 0;
            }
        }

        ALOGV("selecting track %zu", i);

        err = extractor->selectTrack(i);
        CHECK_EQ(err, (status_t)OK);

        ssize_t newTrackIndex = muxer->addTrack(format);
        if (newTrackIndex < 0) {
            fprintf(stderr, "%s track (%zu) unsupported by muxer\n",
                    isAudio ? "audio" : "video",
                    i);
        } else {
            trackIndexMap.add(i, newTrackIndex);
        }
    }

    int64_t muxerStartTimeUs = ALooper::GetNowUs();

    bool sawInputEOS = false;

    size_t trackIndex = -1;
    sp<ABuffer> newBuffer = new ABuffer(bufferSize);

    muxer->setOrientationHint(rotationDegrees);
    muxer->start();

    while (!sawInputEOS) {
        status_t err = extractor->getSampleTrackIndex(&trackIndex);
        if (err != OK) {
            ALOGV("saw input eos, err %d", err);
            sawInputEOS = true;
            break;
        } else if (trackIndexMap.indexOfKey(trackIndex) < 0) {
            // ALOGV("skipping input from unsupported track %zu", trackIndex);
            extractor->advance();
            continue;
        } else {
            // ALOGV("reading sample from track index %zu\n", trackIndex);
            err = extractor->readSampleData(newBuffer);
            CHECK_EQ(err, (status_t)OK);

            int64_t timeUs;
            err = extractor->getSampleTime(&timeUs);
            CHECK_EQ(err, (status_t)OK);

            sp<MetaData> meta;
            err = extractor->getSampleMeta(&meta);
            CHECK_EQ(err, (status_t)OK);

            uint32_t sampleFlags = 0;
            int32_t val;
            if (meta->findInt32(kKeyIsSyncFrame, &val) && val != 0) {
                // We only support BUFFER_FLAG_SYNCFRAME in the flag for now.
                sampleFlags |= MediaCodec::BUFFER_FLAG_SYNCFRAME;

                // We turn on trimming at the sync frame.
                if (enableTrim && timeUs > trimStartTimeUs &&
                    timeUs <= trimEndTimeUs) {
                    if (trimStarted == false) {
                        trimOffsetTimeUs = timeUs;
                    }
                    trimStarted = true;
                }
            }
            // Trim can end at any non-sync frame.
            if (enableTrim && timeUs > trimEndTimeUs) {
                trimStarted = false;
            }

            if (!enableTrim || (enableTrim && trimStarted)) {
                err = muxer->writeSampleData(newBuffer,
                                             trackIndexMap.valueFor(trackIndex),
                                             timeUs - trimOffsetTimeUs, sampleFlags);
            }

            extractor->advance();
        }
    }

    muxer->stop();
    newBuffer.clear();
    trackIndexMap.clear();

    int64_t elapsedTimeUs = ALooper::GetNowUs() - muxerStartTimeUs;
    fprintf(stderr, "SUCCESS: muxer generate the video in %" PRId64 " ms\n",
            elapsedTimeUs / 1000);

    return 0;
}