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Diffstat (limited to 'src/devices/media/oem.jd')
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diff --git a/src/devices/media/oem.jd b/src/devices/media/oem.jd new file mode 100644 index 00000000..a271ecd5 --- /dev/null +++ b/src/devices/media/oem.jd @@ -0,0 +1,162 @@ +page.title=OEM Dependencies for Media Resource Manager +@jd:body + +<!-- + Copyright 2015 The Android Open Source Project + + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. +--> +<div id="qv-wrapper"> + <div id="qv"> + <h2>In this document</h2> + <ol id="auto-toc"> + </ol> + </div> +</div> + +<p>This document is intended to help original equipment manufacturers (OEMs) +properly implement support for Android media resource manager and related APIs.</p> + +<h2 id=1_max_concurrent_codec_instances>1. Max concurrent codec instances</h2> + +<p>The <code>CodecCapabilities.getMaxSupportedInstances</code> interface +returns the maximum number of supported concurrent codec instances.</p> + +<p>The CTS test +<code>testGetMaxSupportedInstances(android.media.cts.MediaCodecCapabilitiesTest)</code> +is used to enforce the proper maximum is set in +<code>/etc/media_codecs.xml</code>.</p> + +<p>Here is an example:</p> + +<pre> +... +<MediaCodecs> + ... + <Encoders> + <MediaCodec name="OMX.<em><vendor></em>.video.encoder.avc" type="video/avc" > + ... + <Limit name="concurrent-instances" max="13" /> + </MediaCodec> + ... + </Encoders> + ... +</MediaCodecs> +</pre> + +<p>OEMs can use this test to generate the concurrent limits that pass the test. +To do this:</p> + + <ol> + <li>Run the test first using cts-tradefed. + <li>Evaluate the resulting failure message. Here is an example: + +<pre> +There was 1 failure: +1) testGetMaxSupportedInstances(android.media.cts.MediaCodecCapabilitiesTest) +junit.framework.AssertionFailedError: In order to pass the test, please publish +following codecs' concurrent instances limit in /etc/media_codecs.xml: +<MediaCodec name="OMX.<em><vendor></em>.video.encoder.mpeg4" type="video/mp4v-es" > + <Limit name="concurrent-instances" max="13" /> +</MediaCodec> +<MediaCodec name="OMX.<em><vendor></em>.video.encoder.h263" type="video/3gpp" > + <Limit name="concurrent-instances" max="13" /> +</MediaCodec> +<MediaCodec name="OMX.<em><vendor></em>.video.encoder.avc" type="video/avc" > + <Limit name="concurrent-instances" max="13" /> +</MediaCodec> +<MediaCodec name="OMX.<em><vendor></em>.video.encoder.vp8" type="video/x-vnd.on2.vp8" > + <Limit name="concurrent-instances" max="13" /> +</MediaCodec> +<MediaCodec name="OMX.<em><vendor></em>.video.decoder.avc" type="video/avc" > + <Limit name="concurrent-instances" max="13" /> +</MediaCodec> +<MediaCodec name="OMX.<em><vendor></em>.video.decoder.avc.secure" type="video/avc" > + <Limit name="concurrent-instances" max="4" /> +</MediaCodec> +<MediaCodec name="OMX.<em><vendor></em>.video.decoder.mpeg4" type="video/mp4v-es" > + <Limit name="concurrent-instances" max="12" /> +</MediaCodec> +<MediaCodec name="OMX.<em><vendor></em>.video.decoder.h263" type="video/3gpp" > + <Limit name="concurrent-instances" max="12" /> +</MediaCodec> +<MediaCodec name="OMX.<em><vendor></em>.video.decoder.vp8" type="video/x-vnd.on2.vp8" > + <Limit name="concurrent-instances" max="12" /> +</MediaCodec> +</pre> + + <li>Add the <code>concurrent-instances</code> lines suggested in the test +failure message to the <code>/etc/media_codecs.xml</code> file. + + <li>Re-run the test to verify its success. + </ol> + +<h2 id=2_achievable_frame_rates_for_video_codecs>2. Achievable frame rates for video codecs</h2> +<p>The <code>VideoCapabilities.getAchievableFrameRatesFor</code> interface +returns the range of achievable video frame rates for a video size. This +information must be provided by the OEM for each device via an XML file placed at +<code>/etc/media_codecs_performance.xml</code>. These settings are tested by +the <code>com.android.cts.videoperf.VideoEncoderDecoderTest</code> and +<code>android.media.cts.VideoDecoderPerfTest</code> CTS tests.</p> + +<p>OEMs can use the CTS tests to generate the XML files that pass the tests. To do this:</p> + <ol> + <li>Run the tests first using cts-tradefed. Given the +variability of Android performance, it is recommended the tests are run +multiple times to get more accurate minimum and maximum values. + <li>Use the provided <code>get_achievable_rates.py</code> script to +generate the XML file. + <li>Place the XML file at: <code>/etc/media_codecs_performance.xml</code><br> +This is usually done by placing the XML file in the device project +(device/<em><vendor></em>/<em><product></em>) and adding a +<code>PRODUCT_COPY_FILES</code> line to <code>device.mk</code> like so: +<pre> +PRODUCT_COPY_FILES += \ +... + device/moto/shamu/media_codecs.xml:system/etc/media_codecs.xml \ ++ device/moto/shamu/media_codecs_performance.xml:system/etc/media_codecs_performance.xml +</pre> + <li>Re-run the performance tests to verify their success. + </ol> + +<h2 id=3_co-exist_of_secure_codec_and_non-secure_codec>3. Co-exist of secure codec and non-secure codec</h2> + +<ul> + <li>supports-secure-with-non-secure-codec — +If the instance of secure codec and the instance of non-secure codec can’t +co-exist at the same time, that should be indicated as global setting in the +<code>media_codecs.xml</code> file. +<pre> +<MediaCodecs> + <Settings> + <Setting name="supports-secure-with-non-secure-codec" value="false" /> + </Settings> + <Encoders> +… +</pre> + <li>supports-multiple-secure-codecs — +If co-exist of multiple secure codec instances is not supported, that should be +indicated as a global setting in the <code>media_codecs.xml</code> file. +<pre> +<MediaCodecs> + <Settings> + <Setting name="supports-multiple-secure-codecs" value="false" /> + </Settings> + <Encoders> +… +</pre> + <li>Note that the both settings are true by default, meaning if they are supported, +there’s no need to add the setting line to the <code>media_codecs.xml</code>. + <li>The <code>ResourceManagerTest</code> CTS tests may fail if these two settings were not set +properly. +</ul> |