Add support for cqp setting in Export dialog

Accept "cqp" setting in Advanced options of the Export dialog.
Syntax is similar to CRF in the Bit Rate field, "N cqp", where N is
integer from 0 to 63.

src/windows/export.py

@@ -668,23 +668,23 @@ def convert_to_bytes(self, BitRateString):
                 raw_number = locale.atof(raw_number_string)
 
                 if "kb" in raw_measurement:
-                    measurement = "kb"
+                    # Kbit to bytes
                     bit_rate_bytes = raw_number * 1000.0
 
                 elif "mb" in raw_measurement:
-                    measurement = "mb"
+                    # Mbit to bytes
                     bit_rate_bytes = raw_number * 1000.0 * 1000.0
 
-                elif "crf" in raw_measurement:
-                    measurement = "crf"
+                elif ("crf" in raw_measurement) or ("cqp" in raw_measurement):
+                    # Just a number
                     if raw_number > 63:
                         raw_number = 63
                     if raw_number < 0:
                         raw_number = 0
                     bit_rate_bytes = raw_number
 
                 elif "qp" in raw_measurement:
-                    measurement = "qp"
+                    # Just a number
                     if raw_number > 255:
                         raw_number = 255
                     if raw_number < 0:
@@ -886,11 +886,12 @@ def accept(self):
             else:
                 # Muxing options for mp4/mov
                 w.SetOption(openshot.VIDEO_STREAM, "muxing_preset", "mp4_faststart")
-                # Set the quality in case crf was selected
+                # Set the quality in case crf, cqp or qp was selected
                 if "crf" in self.txtVideoBitRate.text():
                     w.SetOption(openshot.VIDEO_STREAM, "crf", str(int(video_settings.get("video_bitrate"))) )
-                # Set the quality in case qp was selected
-                if "qp" in self.txtVideoBitRate.text():
+                elif "cqp" in self.txtVideoBitRate.text():
+                    w.SetOption(openshot.VIDEO_STREAM, "cqp", str(int(video_settings.get("video_bitrate"))) )
+                elif "qp" in self.txtVideoBitRate.text():
                     w.SetOption(openshot.VIDEO_STREAM, "qp", str(int(video_settings.get("video_bitrate"))) )