Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_70537 ( "Frame size" text, "Width" real, "Height" real, "Mpix" real, "Aspect Ratio" text, "Maximum fps" real, "Maximum fps HDRx" real, "least compression at 24 fps" text, "least compression at maximum fps" text )

### Question ###
What is the sum of Mpix with a maximum fps HDRX of less than 12 with a width larger than 5120?

### Accurate SQL ###

SELECT SUM("Mpix") FROM table_70537 WHERE "Maximum fps HDRx" < '12' AND "Width" > '5120'