Dialogic 6.2 manual Strip parameters infopkts

The Bfv API Functions

The strip parameters infopkts:

INFOPKT_ASCII_STRIP_PARAMETERS

INFOPKT_G3_STRIP_PARAMETERS

define the actual strips of data that make up a page and must precede an ASCII or G3 data type infopkt only to change the default or previously applied strip parameter values (see Volume 6, Appendix E in the Bfv API Reference Manual for default values). Dialogic, however, recommends that you include a strip parameter infopkt whenever you define a strip, even if the default values are appropriate for the strip. Strip parameters include the basic format of the data (that is, ASCII or G3 data) and presentation parameters such as vertical resolution, width, and, in the case of ASCII, left and right margins.

Strip parameters ensure that the strip data is sent out properly and the received fax is displayed with the proper proportions. The module converts strip data to the proper vertical resolution before transmitting it.

For example, if the T.30 document resolution is set to fine resolution, and a G3 strip is in normal resolution, the firmware converts the data to fine resolution, replicating each line. Likewise, if the T.30 document resolution is set to normal resolution, and a G3 strip is in fine resolution, the firmware converts the data to normal resolution, removing every other line. If the T.30 document resolution and a G3 strip resolution are the same, the module transmits the data as-is. The vertical resolution of the strip data informs the module when to convert data and how to convert it.

When ASCII strip data is sent to the module, the current vertical resolution parameter is set to normal, even if an INFOPKT_ASCII_STRIP_PARAMETERS infopkt is inserted into the infopkt stream. Thus the resolution of any G3 strip data, encountered later in the infopkt stream, is also assumed to be normal, unless otherwise specified by an accompanying INFOPKT_G3_STRIP_PARAMETERS infopkt.

When two consecutive G3 strips of data are sent to the module, an INFOPKT_G3_STRIP_PARAMETERS infopkt must be inserted between them. Since each G3 strip data ends with an RTC marker (six consecutive end-of-line codes) that is interpreted by the module as the end of the strip of data, an INFOPKT_G3_STRIP_PARAMETERS infopkt is required to indicate the beginning of the second G3 strip.

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