A computer-implemented method for real-time transmission of data streams from a video transmitting device adapted to generate and transmit at least: (i) a first data stream, the first data stream for providing to a browser and comprising at least one preview frame, and (ii) a second data stream, the first data stream and the second data stream generated based on the same captured video stream, the second data stream having a higher bitrate relative to the first data stream, the method comprising: receiving, from a browser, data representing at least one stream parameter and acknowledgements from the browser that a preview frame has been received; generating, by a processor, electronic instructions based at least on the received data, the electronic instructions for causing modification of a transmission framerate associated with the first data stream based at least in part on the at least one stream parameter; calculating, by the processor, a difference between the number of video preview frames sent and the number of acknowledgements that those frames have been received; causing, by the processor, the video transmitting device to (i) decrease the transmission framerate when the difference between the number of acknowledgements from the browser and the number of frames transmitted is greater than a predefined number, and (ii) increase a transmission framerate when the difference between the number of acknowledgements from the browser and the number of frames transmitted is less than the predefined number, wherein the decrease or increase of the transmission framerate is performed as an integer decimation of an initial transmission framerate; and communicating, by the processor, the electronic instructions to the video transmitting device, the video transmitting device configured for receiving the electronic instructions and modifying the transmission framerate of the first data stream; wherein the modification of the transmission framerate associated with the first data stream changes a utilization of transmission bandwidth by the first and the second data streams, wherein the transmission bandwidth is shared between the transmission of the first data stream and the transmission of the second data stream, the second data stream having a higher latency relative to both the captured video stream and the first data stream. receiving, from a browser, data representing at least one stream parameter and acknowledgements from the browser that a preview frame has been received; generating, by a processor, electronic instructions based at least on the received data, the electronic instructions for causing modification of a transmission framerate associated with the first data stream based at least in part on the at least one stream parameter; calculating, by the processor, a difference between the number of video preview frames sent and the number of acknowledgements that those frames have been received; causing, by the processor, the video transmitting device to (i) decrease the transmission framerate when the difference between the number of acknowledgements from the browser and the number of frames transmitted is greater than a predefined number, and (ii) increase a transmission framerate when the difference between the number of acknowledgements from the browser and the number of frames transmitted is less than the predefined number, wherein the decrease or increase of the transmission framerate is performed as an integer decimation of an initial transmission framerate; and communicating, by the processor, the electronic instructions to the video transmitting device, the video transmitting device configured for receiving the electronic instructions and modifying the transmission framerate of the first data stream; wherein the modification of the transmission framerate associated with the first data stream changes a utilization of transmission bandwidth by the first and the second data streams, wherein the transmission bandwidth is shared between the transmission of the first data stream and the transmission of the second data stream, the second data stream having a higher latency relative to both the captured video stream and the first data stream.