Read a partcular value from json array in php [duplicate]

this is my json :

[{"type": "video/mp4", "label": "1080p", "file": "https://lh3.googleusercontent.com/-7keCcCYcDv1gP1UPTO9lTJWzoldW0WNOnZtIv3P0vQxa2ujVNSAaG1g5tyotkuuDSqGcWcxTI7yyJj3pn2ejTVwnSOLlVqG13XMMXVulW3BIQQcIh6X_PEyz3JxC4ljhV6aS2ROzQ=m37"},{"type": "video/mp4", "label": "720p", "file": "https://lh3.googleusercontent.com/-7keCcCYcDv1gP1UPTO9lTJWzoldW0WNOnZtIv3P0vQxa2ujVNSAaG1g5tyotkuuDSqGcWcxTI7yyJj3pn2ejTVwnSOLlVqG13XMMXVulW3BIQQcIh6X_PEyz3JxC4ljhV6aS2ROzQ=m22"},{"type": "video/mp4", "label": "360p", "file": "https://lh3.googleusercontent.com/-7keCcCYcDv1gP1UPTO9lTJWzoldW0WNOnZtIv3P0vQxa2ujVNSAaG1g5tyotkuuDSqGcWcxTI7yyJj3pn2ejTVwnSOLlVqG13XMMXVulW3BIQQcIh6X_PEyz3JxC4ljhV6aS2ROzQ=m18"}]

i need to echo only the lable:1080p "file" value in php?