| 1 | # media_conv |
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| 2 | A Pyramid web service that converts audio data from WAV to M4A. |
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| 3 | |
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| 4 | ## Dependencies |
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| 5 | * Python version 3.3+ with libraries: |
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| 6 | * pyramid |
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| 7 | * pyramid_debugtoolbar |
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| 8 | * waitress |
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| 9 | |
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| 10 | ## Usage |
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| 11 | The web service has one entry point `media_conv` that responds to HTTP `GET` and `POST` requests. |
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| 12 | |
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| 13 | ###`media_conv` |
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| 14 | |
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| 15 | #### Parameters |
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| 16 | 1. `input_mime_type`: MIME type of input media data at `input_media_url`. |
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| 17 | 2. `jwplayer_file_url_hack`: whether to apply a hack to let JWplayer use media_conv successfully. `jwplayer_file_url_hack` can be `0` (enable) or `1` (disable). |
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| 18 | 3. `input_media_url`: HTTP URL where the input media data can be retrieved from. |
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| 19 | |
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| 20 | #### Response |
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| 21 | A HTTP response with the audio data received after issuing a HTTP `GET` request based on the URL `input_media_url`. |
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| 22 | |
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| 23 | #### Notes |
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| 24 | The version of JW Player used by Annex requires a hack to accept a global identifier URI wherein media_conv is called to return `audio/mp4` audio. |
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| 25 | |
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| 26 | 1. The HTTP request method is `GET`. |
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| 27 | 2. `jwplayer_file_url_hack=1`. |
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| 28 | 3. `input_media_url`... parameter and value combination has (fictional, extra) suffix of `.m4a`. |
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| 29 | 4. The call URI ends with the `input_media_url` parameter and value combination and therefore ends with the `.m4a` string. |
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| 30 | 5. The file `crossdomain.xml` to allow Flash cross-domain scripting is at the document root of the web site where the, if Annex runs from a different FQDN. |
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| 31 | |
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| 32 | #### Example usages (on Unix, with `curl`) |
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| 33 | Advised usage: |
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| 34 | |
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| 35 | curl -v -X POST \ |
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| 36 | 'http://infra.clarin.eu/app/media_conv?input_mime_type=audio/x-wav&jwplayer_file_url_hack=0&output_mime_type=audio/mp4&input_media_url=http://infra.clarin.eu/tmp/maus-pipeline/g001acn1_000_AAJ_1.wav' \ |
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| 37 | > /tmp/g001acn1_000_AAJ_1.m4a ; |
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| 38 | |
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| 39 | As used by Annex/JW Player, and on the server where the web application runs (localhost): |
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| 40 | |
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| 41 | curl -v -X GET \ |
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| 42 | 'http://127.0.0.1:6543/media_conv?input_mime_type=audio/x-wav&jwplayer_file_url_hack=1&output_mime_type=audio/mp4&input_media_url=http://infra.clarin.eu/tmp/maus-pipeline/g001acn1_000_AAJ_1.wav.m4a' \ |
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| 43 | > /tmp/g001acn1_000_AAJ_1.m4a ; |
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| 44 | |
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| 45 | ## Future work |
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| 46 | |
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| 47 | === Goals === |
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| 48 | 1. Make more robust: currently the conversion process creates a temporary file for each request that isn't being cleaned up. Move to a performant and stable database/key-value store. |
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| 49 | 2. Handle more types of media. |
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