A system and method are provided for selecting frames of a compressed video stream that may be used for client-side watermarking. In general, a content source evaluates a number of Intra-Frames (I-Frames) in the compressed video stream using a sample watermark that is similar to actual watermarks that may be used for client-side watermarking. More specifically, each of a number of I-Frames in the compressed video stream is evaluated by first watermarking the I-Frame with the sample watermark. Associated frames in the compressed video stream are then decoded using the watermarked I-Frame. An error value for the decoded video frames is then computed. If the error value is outside of a predetermined error threshold range, the I-Frame is selected as an I-Frame that may be used for client-side watermarking.