ffmpeg-tutorial

This repository contains files from an FFmpeg tutorial originally written by Stephen Dranger ([email protected]). The files have been updated to work with the most recent version of FFmpeg (see VERSION.txt for the most recent version at the time of writing). The updates were performed with an effort to modify as little code as possible, so that the original code and tutorial descriptions could be easily consulted.

The code from the original tutorial and the accompanying description is located here.

Main changes

• Renamed includes, e.g. ffmpeg/avcodec.h --> libavcodec/avcodec.h
• Work around deprecated functions and symbols (see below)
• Initializing pointers to NULL on declaration. Some FFmpeg functions (e.g. avformat_open_input) now segfault when given uninitialized pointers as input.
• Removed tutorial08.c, which introduced software scaling (as opposed to using the img_convert method). img_convert has been deprecated and is no longer available, so these new tutorials use software scaling from the very beginning, and a separate tutorial is not necessary.

Deprecated Functions and Symbols

This section describes the changes made to work around deprecated functions and symbols, in the format: before --> after. In some cases, a simple rename sufficed (e.g. dump_format), but in others, more significant changes to the code were required (e.g. avcodec_decode_audio2). Consult the diffs for each respective tutorial to see exactly what has changed since the original version of the tutorial.

• av_open_input_file --> avformat_open_input
• av_find_stream_info --> avformat_find_stream_info
• dump_format --> av_dump_format
• CODEC_TYPE_VIDEO --> AVMEDIA_TYPE_VIDEO
• avcodec_open --> avcodec_open2
• avcodec_decode_video --> avcodec_decode_video2
• img_convert --> sws_scale
• av_close_input_file --> avformat_close_input
• avcodec_decode_audio2 --> avcodec_decode_audio4
• CODEC_TYPE_AUDIO --> AVMEDIA_TYPE_AUDIO
• url_set_interrupt_cb --> avio_open2
• url_ferror --> check attribute is->pFormatCtx->pb->error
• pstrcpy --> av_strlcpy

Building and Running

First, make sure you have a recent installation of FFmpeg. It's recommended that you build FFmpeg from source as described in this link.

To build the tutorials:

git clone [email protected]:chelyaev/ffmpeg-tutorial.git
cd ffmpeg-tutorial
make

To run a tutorial, first make sure that your ffmpeg installation is on your $LD_LIBRARY_PATH and then:

bin/tutorial01.out