README: Fix typo, improve wording

Not much of substance changed. I just noticed a typo and so re-read
everything and adjusted some language.
This commit is contained in:
Will Storey
2017-03-14 10:40:13 -07:00
parent aba249aa62
commit 763dc8fd38

View File

@@ -1,28 +1,29 @@
videostreamer provides a way to stream video from an input source to HTTP. It
remuxes a given video input into an MP4 container which it then streams
endlessly to any connecting clients. This provides the ability to stream an
input source that may have limited connections or not accessible via HTTP.
remuxes a given video input into an MP4 container which it then streams to any
connecting clients. This provides the ability to stream an input source that
may have limited connections, is not accessible via HTTP, or is not easily
embeddable in a website.
# Background
A friend has a camera that publishes an RTSP feed containing h264 video. It
permits a limited number of connections, and being RTSP is not easily
accessible on the web, such as in a regular HTML5 `<video>` element. This
project solves both of these problems. It reads the RTSP feed as input, remuxes
the h264 video into an MP4 container, and streams that to HTTP clients. No
matter how many clients are streaming the video, videostreamer only opens one
RTSP connection.
accessible on the web, such as in a regular HTML5 `<video>` element.
videostreamer solves both of these problems. It reads the RTSP feed as input,
remuxes the h264 video into an MP4 container, and streams it to HTTP clients.
No matter how many clients are streaming the video, videostreamer only opens
one RTSP connection.
Happily, browsers support h264 inside an MP4 container, so no transcoding is
Happily, browsers support h264 in an MP4 container, so no transcoding is
necessary. However, in order to stream the MP4, it is fragmented using
libavformat's `frag_keyframe` option. I found that in Firefox, I also had to
libavformat's `frag_keyframe` option. I found that for Firefox I also had to
set the `empty_moov` option.
# Difference from audiostreamer
I have a similar project for streaming audio called
I have a project for streaming audio called
[audiostreamer](https://github.com/horgh/audiostreamer). I wrote it before this
one, and seeing it was succesful and gave me experience with the ffmpeg
one, and seeing it was successful and gave me experience with the ffmpeg
libraries, I decided to build this too.
Initially I was going to make one larger project to stream either video or audio
@@ -35,11 +36,11 @@ way to send to every client. I found that I could not gain access to the header
from the libavformat API. Second, I was not able to read individual frames out
and send them independently like I could do with MP3. This meant it was
impossible to know where in the MP4 container's output I could begin sending to
a client that connected when another client was already streaming.
a new client when another client was already streaming.
Since it became clear that I would have to structure the program quite
differently, and I was happy with how audiostreamer was, I decided to split them
into two projects.
differently, and I was happy with how audiostreamer was, I decided to build
videostreamer as a separate project.
# Requirements