ngryman/ribs

/*!
 * ribs
 * Copyright (c) 2013-2014 Nicolas Gryman <ngryman@gmail.com>
 * LGPL Licensed
 */

#include "encode.h"
#include "../image.h"

using namespace std;
using namespace v8;
using namespace node;
using namespace ribs;

OPERATION_PREPARE(Encode, {
    image = ObjectWrap::Unwrap<Image>(args.This());

    // check if image is empty
    if (image->Matrix().empty()) throw invalid_argument("empty image");

    format  = FromV8String(args[0]);
    quality = args[1]->Uint32Value();
})

OPERATION_CLEANUP(Encode, {})

OPERATION_PROCESS(Encode, {
    try {
        vector<int> params;

        // quality
        if (quality > 0) {
            params.push_back("jpg" == format ? CV_IMWRITE_JPEG_QUALITY : CV_IMWRITE_PNG_COMPRESSION);

            // normalize png quality for OCV.
            // RIBS takes a [0,100] value, OCV takes a [0,9] value.
            if ("png" == format)
                quality = quality * 90 / 1000;

            params.push_back(quality);
        }

        // encode
        cv::imencode("." + format, image->Matrix(), outVec);
    }
    catch (...) {
        // OCV uses assertion to handle errors, thus the message is not very explicit.
        // we simply do nothing and check against outMat.
    }

    // empty matrix, set error
    if (outVec.empty()) {
        error = "operation error: encode";
    }
})

OPERATION_VALUE(Encode, {
    return NanNewBufferHandle(reinterpret_cast<char*>(&outVec[0]), outVec.size());
})