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Original commit message from CVS: * docs/design/draft-klass.txt: Add example that needs more thinking. * docs/design/draft-missing-plugins.txt: More thoughts about wtrapper plugins. * docs/random/ensonic/embedded.txt: * docs/random/ensonic/profiling.txt: More design work.
57 lines
2.1 KiB
Text
57 lines
2.1 KiB
Text
$Id$
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= embedded =
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== index handling ==
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For avidemux I currently have a big patch doing memory optimized index handling.
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It basically thins out the index to save memory. Right now it only keeps index
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entries marked with the avi keyframe flag.
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In gstreamer core we have some indexing objects. They are curently used nowhere.
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The idea is to use them and to make the index strategy plugable or configurable
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at run time.
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The challenge is then to rewrite muxers and demuxers to use them instead of the
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built in index logic.
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This way the different requirements of desktop and embedded platforms could be
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encapsulated in the indexer strategy.
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== ranking ==
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Autopluggers like playbin and decodebin use the element caps plus static ranks
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to create piplines.
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The rank of an elemnt right now refers to the quality/maturity of the element.
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Elements with higher rank should be functionaly more complete. If we have
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multiple elements that are feature complete there is a draw.
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There are more decission criteria thinkable:
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* target processor (CPU,DSP,GPU)
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* ressource usage (CPU, memory)
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* license (proprietary, open source)
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* quality (in terms of the audio/image quality)
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One problem of taking criteria like quality and performance into account when
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autoplugging, is that elements might have objects-properties that influence
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them.
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Beside adding more ranking criteria, we might consider adding an overridable
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mechanism for picking elements (basically registry filters that not decide on
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the base of ranks). Applications might choose the filter mechanism based on the
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use-case (which gstreamer not know right now).
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== g_malloc vs. g_try_malloc ==
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g_malloc/g_new should not be used when allocating space of a size that is
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derived from a value found in the file. Instead one should use g_try_malloc or
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g_try_new and check the return value.
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$ find . -name "*.c" -exec grep "g_malloc" {} \; | wc -l
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190
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$ find . -name "*.c" -exec grep "g_try_malloc" {} \; | wc -l
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0
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$ find . -name "*.c" -exec grep "g_new" {} \; | wc -l
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398
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$ find . -name "*.c" -exec grep "g_try_new" {} \; | wc -l
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3
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This is not strickly related to embedded, but its easier to crash gstreamer on
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embedded this way.
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