framecache.C

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#include "clip.h"
#include "framecache.h"
#include "mutex.h"
#include "vframe.h"


#include <math.h>

FrameCacheItem::FrameCacheItem()
{
        data = 0;
        position = 0;
        frame_rate = (double)30000.0 / 1001;
        age = 0;
}

FrameCacheItem::~FrameCacheItem()
{
        if(data) delete data;
}
















FrameCache::FrameCache()
{
        lock = new Mutex("FrameCache::lock");
        max_bytes = 0;
        current_age = 0;
}

FrameCache::~FrameCache()
{
        items.remove_all_objects();
        delete lock;
}


// Returns 1 if frame exists in cache and copies it to the frame argument.
int FrameCache::get_frame(VFrame *frame, 
        int64_t position,
        double frame_rate)
{
        lock->lock("FrameCache::get_frame");
        int item_number = -1;

        if(frame_exists(frame,
                position, 
                frame_rate,
                &item_number))
        {
                FrameCacheItem *item = items.values[item_number];
                if(item->data) frame->copy_from(item->data);
                item->age = current_age;
                current_age++;
        }

        lock->unlock();
        if(item_number >= 0) return 1;
        return 0;
}


VFrame* FrameCache::get_frame_ptr(int64_t position,
        double frame_rate,
        int color_model,
        int w,
        int h)
{
        lock->lock("FrameCache::get_frame");
        int item_number = -1;
        FrameCacheItem *item = 0;
        if(frame_exists(position,
                frame_rate,
                color_model,
                w,
                h,
                &item_number))
        {
                item = items.values[item_number];
                item->age = current_age;
                current_age++;
        }


        if(item)
                return item->data;
        else
        {
                lock->unlock();
                return 0;
        }
}

void FrameCache::unlock()
{
    lock->unlock();
}

// Puts frame in cache if enough space exists and the frame doesn't already
// exist.
void FrameCache::put_frame(VFrame *frame, 
        int64_t position,
        double frame_rate,
        int use_copy)
{
        lock->lock("FrameCache::put_frame");
        int item_number = -1;
        if(frame_exists(frame,
                position, 
                frame_rate,
                &item_number))
        {
                FrameCacheItem *item = items.values[item_number];
                item->age = current_age;
                current_age++;
                lock->unlock();
                return;
        }


        FrameCacheItem *item = new FrameCacheItem;

        if(use_copy)
        {
                item->data = new VFrame(*frame);
        }
        else
        {
                item->data = frame;
        }

        item->position = position;
        item->frame_rate = frame_rate;
        item->age = current_age;

        items.append(item);
        current_age++;
        lock->unlock();
}




int FrameCache::frame_exists(VFrame *format,
        int64_t position, 
        double frame_rate,
        int *item_return)
{
        for(int i = 0; i < items.total; i++)
        {
                FrameCacheItem *item = items.values[i];
                if(item->position == position &&
                        EQUIV(item->frame_rate, frame_rate) &&
                        format->equivalent(item->data))
                {
                        *item_return = i;
                        return 1;
                }
        }
        return 0;
}

int FrameCache::frame_exists(int64_t position, 
        double frame_rate,
        int color_model,
        int w,
        int h,
        int *item_return)
{
        for(int i = 0; i < items.total; i++)
        {
                FrameCacheItem *item = items.values[i];
                if(item->position == position &&
                        EQUIV(item->frame_rate, frame_rate) &&
                        color_model == item->data->get_color_model() &&
                        w == item->data->get_w() &&
                        h == item->data->get_h())
                {
                        *item_return = i;
                        return 1;
                }
        }
        return 0;
}

// Calculate current size of cache in bytes
int64_t FrameCache::get_memory_usage()
{
        int64_t result = 0;
        lock->lock("FrameCache::get_memory_usage");
        for(int i = 0; i < items.total; i++)
        {
                FrameCacheItem *item = items.values[i];
                result += item->data->get_data_size();
        }
        lock->unlock();
        return result;
}

int FrameCache::delete_oldest()
{
        int64_t oldest = 0x7fffffff;
        int oldest_item = -1;

        lock->lock("FrameCache::delete_oldest");
        for(int i = 0; i < items.total; i++)
        {
                if(items.values[i]->age < oldest)
                {
                        oldest = items.values[i]->age;
                        oldest_item = i;
                }
        }

        if(oldest_item >= 0)
        {
                items.remove_object_number(oldest_item);
                lock->unlock();
                return 0;
        }
        lock->unlock();
        return 1;
}

void FrameCache::dump()
{
        lock->lock("FrameCache::dump");
        printf("FrameCache::dump 1 %d\n", items.total);
        for(int i = 0; i < items.total; i++)
        {
                FrameCacheItem *item = items.values[i];
                printf("  position=%lld frame_rate=%f age=%d size=%d\n", 
                        item->position, 
                        item->frame_rate, 
                        item->age,
                        item->data->get_data_size());
        }
        lock->unlock();
}

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