[FFmpeg-devel] [PATCH 2/6] Frame-based multithreading framework using pthreads

[Justin Ruggles]

On 02/05/2011 06:38 PM, Alexander Strange wrote:

> On Sat, Feb 5, 2011 at 1:10 PM, Justin Ruggles <justin.ruggles at gmail.com> wrote:
>> On 02/05/2011 12:28 AM, Alexander Strange wrote:
>>
>>> +/**
>>> + * Context used by codec threads and stored in their AVCodecContext thread_opaque.
>>> + */
>>> +typedef struct PerThreadContext {
>>> +    struct FrameThreadContext *parent;
>>> +
>>> +    pthread_t      thread;
>>> +    pthread_cond_t input_cond;      ///< Used to wait for a new frame from the main thread.
>>> +    pthread_cond_t progress_cond;   ///< Used by child threads to wait for progress to change.
>>> +    pthread_cond_t output_cond;     ///< Used by the main thread to wait for frames to finish.
>>> +
>>> +    pthread_mutex_t mutex;          ///< Mutex used to protect the contents of the PerThreadContext.
>>> +    pthread_mutex_t progress_mutex; ///< Mutex used to protect frame progress values and progress_cond.
>>> +
>>> +    AVCodecContext *avctx;          ///< Context used to decode frames passed to this thread.
>>> +
>>> +    AVPacket       avpkt;           ///< Input frame (for decoding) or output (for encoding).
>>> +    int            allocated_buf_size; ///< Size allocated for avpkt.data
>>> +
>>> +    AVFrame picture;                ///< Output picture (for decoding) or input (for encoding).
>>> +    int     got_picture;            ///< The output of got_picture_ptr from the last avcodec_decode_video() call.
>>> +    int     result;                 ///< The result of the last codec decode/encode() call.
>>
>>
>> Here and many other place use the term "picture" a lot for the AVFrame.
>>  I understand the current code is focused on video decoding, but it
>> would be nice if the framework (especially the public parts) was more
>> neutral by using the term "frame" instead of "picture" so it will make
>> sense for audio at some point as well.
> 
> I tried to use "frame" for encoded data and "picture" for decoded data.
> I can use "packet" for the first, but using "frame" for the second
> made me uncomfortable because field pictures aren't "frames". That's
> why I stuck to "picture".
> 
> I don't mind changing it to "packet" for encoded and "frame" for
> decoded though, it matches the data types. Is that OK?


Yes, that sounds better.

Thanks,
Justin