I am working on a video streaming project where I need to apply a dynamic watermarking (e.g., username and email) in real-time for security purposes. The video is being streamed in DASH format, and the segment files are in .m4s format generated via FFmpeg.
Challenges:
- Is it possible to directly apply dynamic watermarking to .m4s segment files?
- Are there any tools other than FFmpeg that support real-time watermarking of video streams?
Video segments are generated using FFmpeg with the following command:
ffmpeg
.input(video_path)
.output(mpd_path,
format='dash',
map='0',
video_bitrate='2400k',
video_size='1920x1080',
vcodec='libx264',
seg_duration='4', # Sets segment duration to 4 seconds
acodec='copy')
.run()
What I tried: I attempted to use FFmpeg to apply a watermark dynamically to the .m4s files using the drawtext filter, but .m4s files are not always recognized as valid input for FFmpeg operations.
# FFmpeg command to add watermark to m4s file
try:
# FFmpeg processing
out, err = (
ffmpeg
.input(m4s_file_path) # Input the segment file
.filter(
"drawtext",
text=user_info,
fontfile="font/dejavu-sans/DejaVuSans-Bold.ttf",
fontsize=24,
fontcolor="white",
x=10,
y=10
)
.output(
"pipe:", # Stream output as a byte stream
format="mp4", # Output format as MP4 (compatible with MPEG-DASH)
vcodec="libx264",
acodec="copy",
movflags="frag_keyframe+empty_moov"
)
.run(capture_stdout=True, capture_stderr=True)
)
logger.info(f"FFmpeg process completed. stdout length: {len(out)}, stderr: {err.decode('utf-8')}")
logger.error(f"FFmpeg stderr: {err.decode('utf-8')}")
return out # Return the processed video stream data
except ffmpeg.Error as e:
stderr_output = e.stderr.decode('utf-8') if e.stderr else "No stderr available"
logger.error(f"FFmpeg error: {stderr_output}")
raise RuntimeError(f"Error processing video: {stderr_output}")
Error I faced:
video-streaming-backend | [mov,mp4,m4a,3gp,3g2,mj2 @ 0x7f1bf99cc640] Could not find codec parameters for stream 0 (Video: h264 (avc1 / 0x31637661), none(tv, bt709), 1920x1012): unspecified pixel format
video-streaming-backend | Consider increasing the value for the 'analyzeduration' (10000000) and 'probesize' (5000000) options
video-streaming-backend | Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'http://web:8000/media/stream_video/chunks/ec1db006-b488-47ad-8220-79a05bcaae39/segments/init-stream0.m4s':
video-streaming-backend | Metadata:
video-streaming-backend | major_brand : iso5
video-streaming-backend | minor_version : 512
video-streaming-backend | compatible_brands: iso5iso6mp41
video-streaming-backend | encoder : Lavf60.16.100
video-streaming-backend | Duration: N/A, bitrate: N/A
video-streaming-backend | Stream #0:0[0x1](und): Video: h264 (avc1 / 0x31637661), none(tv, bt709), 1920x1012, SAR 1:1 DAR 480:253, 12288 tbr, 12288 tbn (default)
video-streaming-backend | Metadata:
video-streaming-backend | handler_name : VideoHandler
video-streaming-backend | vendor_id : [0][0][0][0]
video-streaming-backend | Stream mapping:
video-streaming-backend | Stream #0:0 (h264) -> drawtext:default
video-streaming-backend | drawtext:default -> Stream #0:0 (libx264)
video-streaming-backend | Press [q] to stop, [?] for help
video-streaming-backend | Cannot determine format of input stream 0:0 after EOF
video-streaming-backend | Error marking filters as finished
video-streaming-backend | Error while filtering: Invalid data found when processing input
video-streaming-backend | [out#0/mp4 @ 0x7f1bf8e73100] Nothing was written into output file, because at least one of its streams received no packets.
video-streaming-backend | frame= 0 fps=0.0 q=0.0 Lsize= 0kB time=N/A bitrate=N/A speed=N/A
video-streaming-backend | Conversion failed!
These errors have left me wondering if .m4s is a viable format for dynamic watermarking. If it's not, what would be the correct approach?