IDvdInfo2::GetDVDTextStringAsUnicode method (strmif.h)
[The feature associated with this page, DirectShow, is a legacy feature. It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation. Those features have been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use MediaPlayer, IMFMediaEngine and Audio/Video Capture in Media Foundation instead of DirectShow, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]
The GetDVDTextStringAsUnicode method retrieves a DVD text string for a specified language, and returns the text string as a Unicode string.
Syntax
HRESULT GetDVDTextStringAsUnicode(
[in] ULONG ulLangIndex,
[in] ULONG ulStringIndex,
[out] WCHAR *pchwBuffer,
[in] ULONG ulMaxBufferSize,
[out] ULONG *pulActualSize,
[out] DVD_TextStringType *pType
);
Parameters
[in] ulLangIndex
Zero-based index of the language. To find the number of text-string languages on the DVD, call IDvdInfo2::GetDVDTextNumberOfLanguages.
[in] ulStringIndex
Zero-based index of the string to retrieve. To find the number of strings for a given language, call IDvdInfo2::GetDVDTextLanguageInfo.
[out] pchwBuffer
Pointer to a buffer that receives the text string. If pchBuffer is NULL, this method returns the size of the string in pulActualSize.
[in] ulMaxBufferSize
Size of the pchBuffer buffer, in WCHARs.
[out] pulActualSize
Receives the actual length of the string in characters, including the terminating NULL.
[out] pType
Receives a member of the DVD_TextStringType enumeration. The value indicates the type of text string, such as movie title or song name. This parameter can also receive values that are not defined in the DVD_TextStringType enumeration.
Return value
Returns one of the following HRESULT values.
| Return code | Description |
|---|---|
|
Success. |
|
Unsupported te |
|
Invalid argument. |
|
An unexpected internal error occurred. |
Remarks
This method supports text strings that are encoded as Unicode or 7-bit ASCII (ISO/IEC 646). If the text string uses ASCII encoding, the method converts the string to a wide-character string. If the text string uses any other character set, the method returns E_FAIL. In that case, you can call IDvdInfo2::GetDVDTextStringAsNative to retrieve the string as a raw byte array. To find the character set, call IDvdInfo2::GetDVDTextLanguageInfo.
The returned string always includes a terminating NULL. If the buffer is smaller than the length of the DVD text string, the string is truncated. To find the required size of the buffer, call the method once with pchBuffer equal to NULL and ulMaxBufferSize equal to zero. The size is returned in pulActualSize. Then allocate a buffer and call the method again.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows XP [desktop apps only] |
| Minimum supported server | Windows Server 2003 [desktop apps only] |
| Target Platform | Windows |
| Header | strmif.h (include Dshow.h) |
| Library | Strmiids.lib |