{"id":398,"date":"2008-06-27T06:02:05","date_gmt":"2008-06-27T04:02:05","guid":{"rendered":"https:\/\/alax.info\/blog\/?p=398"},"modified":"2008-11-24T17:57:08","modified_gmt":"2008-11-24T15:57:08","slug":"ffdshow-is-getting-more-annoying","status":"publish","type":"post","link":"https:\/\/alax.info\/blog\/398","title":{"rendered":"FFDShow is getting more annoying"},"content":{"rendered":"

Surprisingly fast I got new problems having ffdshow<\/a> installed as a part of K-Lite Codec Pack<\/a>. No wonder though because let us take a look at registration information:<\/p>\n

Display Name: @device:sw:{083863F1-70DE-11D0-BD40-00A0C911CE86}\\{0F40E1E5-4F79-4988-B1A9-CC98794E6B55}
\nCLSID: {0F40E1E5-4F79-4988-B1A9-CC98794E6B55}
\nFriendly Name: ffdshow Audio Decoder
\nPath: C:\\Program Files\\K-Lite Codec Pack\\ffdshow\\ffdshow.ax
\nMerit: 0x3fffffff<\/strong><\/p><\/blockquote>\n

Nice merit, ain’t it? What is merit anyway? Let us check at MSDN<\/a>:<\/p>\n

MERIT_PREFERRED = 0x800000,
\nMERIT_NORMAL = 0x600000,
\n…
\nMERIT_HW_COMPRESSOR = 0x100050<\/p><\/blockquote>\n

The highest defined value is 0x00800000, while ffdshow is registered with 0x3FFFFFFF, that is on top of everything. No doubt the developers read Guidelines for Registering Filters<\/a> and decided to get rid of the rest of installed software as unnecessary crap.<\/p>\n

Anyway back to the problem: I had an A-law<\/a> wave file (WAVE_FORMAT_ALAW) to play and make sure its data is valid and quite unexpectedly there was a silence while playing. A quick check confirmed that the sustem has CCITT A-law codec installed, however GraphEdit shown ffdshow Audio Decoder intercepting decoding. Obviously it spoiled the thing!<\/p>\n

Finally I decided it was a right time to take an advantage of IAMGraphBuilderCallback<\/a> interface to detect and reject the bastard.<\/p>\n

<\/p>\n

Luckily it is much easier than it may seem:<\/p>\n

CComQIPtr< IObjectWithSite > pObjectWithSite = pGraphBuilder;
\n__D(pObjectWithSite, E_NOINTERFACE);
\nCObjectPtr< CAmGraphBuilderCallback > pAmGraphBuilderCallback;
\npAmGraphBuilderCallback.Construct();
\n__C(pObjectWithSite->SetSite(pAmGraphBuilderCallback));
\n__C(pGraphBuilder->Render(_FilterGraphHelper::GetFilterPin(pSourceBaseFilter, PINDIR_OUTPUT)));
\n__C(pObjectWithSite->SetSite(NULL));<\/p><\/blockquote>\n

CAmGraphBuilderCallback is active between SetSite calls and it is sufficient to throw ffdshow Audio Decoder away.<\/p>\n

Partial (some header files are excluded) Visual C++.NET 2005 source code can be downloaded here<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"

Surprisingly fast I got new problems having ffdshow installed as a part of K-Lite Codec Pack. No wonder though because let us take a look at registration information: Display Name: @device:sw:{083863F1-70DE-11D0-BD40-00A0C911CE86}\\{0F40E1E5-4F79-4988-B1A9-CC98794E6B55} CLSID: {0F40E1E5-4F79-4988-B1A9-CC98794E6B55} Friendly Name: ffdshow Audio Decoder Path: C:\\Program Files\\K-Lite Codec Pack\\ffdshow\\ffdshow.ax Merit: 0x3fffffff Nice merit, ain’t it? What is merit anyway? Let us… <\/p>\n

Read the full article<\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[11,6,21,13],"tags":[487,485,78,79,91,488],"class_list":["post-398","post","type-post","status-publish","format-standard","hentry","category-atl","category-audio","category-seriously","category-source","tag-atl","tag-audio","tag-directshow","tag-ffdshow","tag-merit","tag-source"],"_links":{"self":[{"href":"https:\/\/alax.info\/blog\/wp-json\/wp\/v2\/posts\/398","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/alax.info\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/alax.info\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/alax.info\/blog\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/alax.info\/blog\/wp-json\/wp\/v2\/comments?post=398"}],"version-history":[{"count":0,"href":"https:\/\/alax.info\/blog\/wp-json\/wp\/v2\/posts\/398\/revisions"}],"wp:attachment":[{"href":"https:\/\/alax.info\/blog\/wp-json\/wp\/v2\/media?parent=398"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/alax.info\/blog\/wp-json\/wp\/v2\/categories?post=398"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/alax.info\/blog\/wp-json\/wp\/v2\/tags?post=398"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}