Commit 8e51900f authored by Jean-Baptiste Kempf's avatar Jean-Baptiste Kempf

Formating of comment

parent 2bf83d25
......@@ -24,8 +24,8 @@
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
* along with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
*****************************************************************************/
/*****************************************************************************
......@@ -37,28 +37,31 @@
* character table identified in the subtitle descriptor.
*
* The spec is quite vague in this area, but what is meant is perhaps that it
* refers to the character index in the codepage belonging to the language specified
* in the subtitle descriptor. Potentially it's designed for widechar
* refers to the character index in the codepage belonging to the language
* specified in the subtitle descriptor. Potentially it's designed for widechar
* (but not for UTF-*) codepages.
*****************************************************************************
*
*****************************************************************************
* Notes on DDS (Display Definition Segment)
* DDS (Display Definition Segment) tells the decoder how the subtitle image relates to
* the video image.
* For SD, the subtitle image is always considered to be for display at 720x576
* (although it's assumed that for NTSC, this is 720x480, this is not documented well)
* Also, for SD, the subtitle image is drawn 'on the glass' (i.e. after video scaling,
+ * letterbox, etc.)
* For 'HD' (subs marked type 0x14/0x24 in PSI), a DDS must be present, and the subs area
* is drawn onto the video area (scales if necessary). The DDS tells the decoder what
* resolution the subtitle images were intended for, and hence how to scale the subtitle
* images for a particular video size
* i.e. if HD video is presented as letterbox, the subs will
* be in the same place on the video as if the video was presented on an HD set
* indeed, if the HD video was pillarboxed by the decoder, the subs may be cut off as
* well as the video. The intent here is that the subs can be placed accurately on the video
* - somthing which was missed in the original spec.
* -----------------------------------------
* DDS (Display Definition Segment) tells the decoder how the subtitle image
* relates to the video image.
* For SD, the subtitle image is always considered to be for display at
* 720x576 (although it's assumed that for NTSC, this is 720x480, this
* is not documented well) Also, for SD, the subtitle image is drawn 'on
* the glass' (i.e. after video scaling, letterbox, etc.)
* For 'HD' (subs marked type 0x14/0x24 in PSI), a DDS must be present,
* and the subs area is drawn onto the video area (scales if necessary).
* The DDS tells the decoder what resolution the subtitle images were
* intended for, and hence how to scale the subtitle images for a
* particular video size
* i.e. if HD video is presented as letterbox, the subs will be in the
* same place on the video as if the video was presented on an HD set
* indeed, if the HD video was pillarboxed by the decoder, the subs may
* be cut off as well as the video. The intent here is that the subs can
* be placed accurately on the video - something which was missed in the
* original spec.
*
* A DDS may also specify a window - this is where the subs images are moved so that the (0,0)
* origin of decode is offset.
......
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