@adrian thanks for your response,
I hope this might help
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[{"error":false,"message":"Added file: thumb2.jpg","file":"\/site\/assets\/files\/1021\/thumb2.jpg","size":58386,"markup":"<li id='file_af653fac12475691aef8963cf2f9ee03' class='ImageOuter gridImage ui-widget'><div class='gridImage__tooltip'><table><tr><th>Dimensions<\/th><td>296x203<\/td><\/tr><tr><th>Filesize<\/th><td>57 kB<\/td><\/tr><tr><th>Variations<\/th><td>0<\/td><\/tr><\/table><\/div>\n\t\t\t<div class='gridImage__overflow'>\n\t\t\t\t<img src=\"\/site\/assets\/files\/1021\/thumb2.260x0.jpg?nc=1487186841\" alt=\"\" data-original=\"\/site\/assets\/files\/1021\/thumb2.jpg?nc=10\" \/>\n\t\t\t<\/div>\n\t\t\t\n\t\t\t\t<div class='gridImage__hover'>\n\t\t\t\t\t<div class='gridImage__inner'>\n\t\t\t\t\t\t<label for='' class='gridImage__trash'>\n\t\t\t\t\t\t\t<input class='gridImage__deletebox' type='checkbox' name='delete_project_thumbnail_af653fac12475691aef8963cf2f9ee03' value='1' title='Delete' \/>\n\t\t\t\t\t\t\t<span class='fa fa-trash-o'><\/span>\n\t\t\t\t\t\t<\/label>\n\t\t\t\t\t\t<a class='gridImage__edit'>\n\t\t\t\t\t\t\t<span>Edit<\/span>\n\t\t\t\t\t\t<\/a>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\n\t\t\t\t<div class='ImageData'>\n\t\t\t\t\t<h2 class='InputfieldImageEdit__name'><span contenteditable='true'>thumb2<\/span>.jpg<\/h2>\n\t\t\t\t\t<span class='InputfieldImageEdit__info'>57 kB, 296×203 <\/span>\n\t\t\t\t\t<div class='InputfieldImageEdit__errors'><\/div>\n\t\t\t\t\t<div class='InputfieldImageEdit__buttons'><small>\n\t\t\t<button type='button' data-href='\/processwire\/page\/image\/edit\/?id=1021&file=1021,thumb2.jpg&rte=0&field=project_thumbnail' class='InputfieldImageButtonCrop ui-button ui-corner-all ui-state-default pw-modal-large pw-modal' data-buttons='#non_rte_dialog_buttons button' data-autoclose='1' data-close='#non_rte_cancel'>\n\t\t\t\t<span class='ui-button-text'>\n\t\t\t\t\t<span class='fa fa-crop'><\/span> Crop\n\t\t\t\t<\/span>\n\t\t\t<\/button>\n\t\t\t<button type='button' data-href='\/processwire\/page\/image\/variations\/?id=1021&file=thumb2.jpg&modal=1&varcnt=varcnt_project_thumbnail_af653fac12475691aef8963cf2f9ee03' class='ui-button ui-corner-all ui-state-default pw-modal-large pw-modal' data-buttons='button'>\n\t\t\t\t<span class='ui-button-text'>\n\t\t\t\t\t<span class='fa fa-files-o'><\/span> \n\t\t\t\t\tVariations\n\t\t\t\t\t<span class='ui-priority-secondary'>(0)<\/span>\n\t\t\t\t<\/span>\n\t\t\t<\/button>\n\t\t\t<\/small><\/div>\n\t\t\t\t\t<div class='InputfieldImageEdit__core'><div class='InputfieldFileDescription'><label for='description_project_thumbnail_af653fac12475691aef8963cf2f9ee03' class='detail'>Description<\/label><input type='text' name='description_project_thumbnail_af653fac12475691aef8963cf2f9ee03' id='description_project_thumbnail_af653fac12475691aef8963cf2f9ee03' value='' \/><\/div><\/div>\n\t\t\t\t\t<div class='InputfieldImageEdit__additional'><\/div>\n\t\t\t\t\t<input class='InputfieldFileSort' type='text' name='sort_project_thumbnail_af653fac12475691aef8963cf2f9ee03' value='0' \/>\n\t\t\t\t\t<input class='InputfieldFileReplace' type='hidden' name='replace_project_thumbnail_af653fac12475691aef8963cf2f9ee03' \/>\n\t\t\t\t\t<input class='InputfieldFileRename' type='hidden' name='rename_project_thumbnail_af653fac12475691aef8963cf2f9ee03' \/>\n\t\t\t\t<\/div>\n\t\t\t<\/li>","replace":false,"overwrite":0}]