phpthumbof not working

 [2014-01-02 13:19:56] (DEBUG @ /index.php) 
<br />Execution time: 0.0001 s
<br />
[2014-01-02 13:19:56] (ERROR @ /index.php) [phpThumbOf] Could not generate thumbnail: assets/img/image.jpg - Debug: Array
(
    [0] => phpThumb() v1.7.11-201108081537 in file "phpthumb.class.php" on line 216
    [1] => setCacheDirectory() starting with config_cache_directory = "/var/www/core/cache/phpthumb/" in file "phpthumb.class.php" on line 958
    [2] => setting config_cache_directory to realpath(/var/www/core/cache/phpthumb) = "/var/www/core/cache/phpthumb" in file "phpthumb.class.php" on line 986
    [3] => setCacheDirectory() starting with config_cache_directory = "/var/www/assets/components/phpthumbof/cache/" in file "phpthumb.class.php" on line 958
    [4] => setting config_cache_directory to realpath(/var/www/assets/components/phpthumbof/cache) = "/var/www/assets/components/phpthumbof/cache" in file "phpthumb.class.php" on line 986
    [5] => setSourceFilename(assets/img/image.jpg) set $this->sourceFilename to "assets/img/image.jpg" in file "phpthumb.class.php" on line 262
    [6] => CleanUpCacheDirectory() set to purge (30.0 days; 100.00 MB; 10,000 files) in file "phpthumb.class.php" on line 673
    [7] => CleanUpCacheDirectory() skipped because "/var/www/assets/components/phpthumbof/cache/phpThumbCacheStats.txt" is recently modified in file "phpthumb.class.php" on line 683
    [8] =>                   file_exists() = 0 in file "phpthumb.class.php" on line 1165
    [9] => file_exists_ignoreopenbasedir() = 0 in file "phpthumb.class.php" on line 1166
    [10] =>                       is_file() = 0 in file "phpthumb.class.php" on line 1167
    [11] =>                 is_executable() = 0 in file "phpthumb.class.php" on line 1168
    [12] => ImageMagickThumbnailToGD() aborting because cannot find convert in $this->config_imagemagick_path (), and `which convert` returned () in file "phpthumb.class.php" on line 1198
    [13] => $AvailableImageOutputFormats = array(text;ico;bmp;wbmp;gif;png;jpeg) in file "phpthumb.class.php" on line 923
    [14] => $this->thumbnailFormat set to $this->config_output_format "jpeg" in file "phpthumb.class.php" on line 934
    [15] => $this->thumbnailFormat set to $this->f "jpeg" in file "phpthumb.class.php" on line 941
    [16] => $this->thumbnailQuality set to "75" in file "phpthumb.class.php" on line 951
    [17] => $this->sourceFilename set to "/var/www/core/model/phpthumb/assets/img/image.jpg" in file "phpthumb.class.php" on line 852
    [18] => phpThumb() v1.7.11-201108081537
http://phpthumb.sourceforge.net

Error messages disabled in file "phpthumb.class.php" on line 3845
    [19] => setCacheDirectory() starting with config_cache_directory = "/var/www/assets/components/phpthumbof/cache" in file "phpthumb.class.php" on line 958
    [20] => setting config_cache_directory to realpath(/var/www/assets/components/phpthumbof/cache) = "/var/www/assets/components/phpthumbof/cache" in file "phpthumb.class.php" on line 986
    [21] => SetCacheFilename() _src set from md5($this->sourceFilename) "/var/www/core/model/phpthumb/assets/img/image.jpg" = "c551c5b6cbf783f74d398e65b1c6b13b" in file "phpthumb.class.php" on line 3238
    [22] => SetCacheFilename() _par set from md5(_farC_zc1_h80_w80_dpi150_q75) in file "phpthumb.class.php" on line 3271
    [23] => starting ExtractEXIFgetImageSize() in file "phpthumb.class.php" on line 3033
    [24] => GetImageSize(/var/www/core/model/phpthumb/assets/img/image.jpg) says image is x in file "phpthumb.class.php" on line 3043
    [25] => GetImageSize("/var/www/core/model/phpthumb/assets/img/image.jpg") failed in file "phpthumb.class.php" on line 3076
    [26] => $this->useRawIMoutput=true after checking $UnAllowedParameters in file "phpthumb.class.php" on line 1315
    [27] => ImageMagickThumbnailToGD() aborting because ImageMagickCommandlineBase() failed in file "phpthumb.class.php" on line 2006
    [28] => ImageMagickThumbnailToGD() failed in file "phpthumb.class.php" on line 3083
    [29] => SetOrientationDependantWidthHeight() starting with ""x"" in file "phpthumb.class.php" on line 3012
    [30] => SetOrientationDependantWidthHeight() setting w="80", h="80" in file "phpthumb.class.php" on line 3028
    [31] => EXIF thumbnail extraction: (size=0; type=""; 0x0) in file "phpthumb.class.php" on line 3140
    [32] => starting SourceImageToGD() in file "phpthumb.class.php" on line 3398
    [33] => starting ImageCreateFromFilename(/var/www/core/model/phpthumb/assets/img/image.jpg) in file "phpthumb.class.php" on line 3313
    [34] => empty $filename or GetImageSize(/var/www/core/model/phpthumb/assets/img/image.jpg) failed in file "phpthumb.class.php" on line 3362
    [35] => Populating $rawimagedata in file "phpthumb.class.php" on line 3370
    [36] => cannot fopen(/var/www/core/model/phpthumb/assets/img/image.jpg) in file "phpthumb.class.php" on line 3381
    [37] => Not using EXIF thumbnail data because $this->exif_thumbnail_data is empty in file "phpthumb.class.php" on line 3469
    [38] => $this->gdimg_source is still empty in file "phpthumb.class.php" on line 3521
    [39] => ImageMagickThumbnailToGD() failed in file "phpthumb.class.php" on line 3523
    [40] => phpThumb() v1.7.11-201108081537
http://phpthumb.sourceforge.net

Error messages disabled in file "phpthumb.class.php" on line 3845
    [41] => SourceImageToGD() failed in file "phpthumb.class.php" on line 342
)