Generate video API

{
    "timeline": {
        "soundtrack": {
            "src": "https://assets.mixkit.co/music/download/mixkit-forest-treasure-138.mp3",
            "effect": "fadeOut"
        },
        "fonts": [
            {
                "src": "https://templates.shotstack.io/basic/asset/font/opensans-regular.ttf"
            }
        ],
        "background": "#000000",
        "tracks": [
            {
                "clips": [
                    {
                        "asset": {
                            "type": "html",
                            "html": "<p>LOREM IPSUM DOLOR SIT AMET, CONSECTETUR ADIPISCING ELIT</p>",
                            "css": "p { font-family: 'Open Sans'; color: #ffffff; font-size: 38px; text-align: center; }",
                            "width": 950,
                            "height": 200
                        },
                        "offset": {
                            "y": -0.1
                        },
                        "start": 0.5,
                        "length": 4.5,
                        "position": "center",
                        "transition": {
                            "in": "fade",
                            "out": "fade"
                        }
                    },
                    {
                        "asset": {
                            "type": "html",
                            "html": "<p>CONSECTETUR ADIPISCING ELIT</p>",
                            "css": "p { font-family: 'Open Sans'; color: #ffffff; font-size: 38px; text-align: center; }",
                            "width": 950,
                            "height": 200
                        },
                        "offset": {
                            "y": -0.1
                        },
                        "start": 5,
                        "length": 4.5,
                        "position": "center",
                        "transition": {
                            "in": "fade",
                            "out": "fade"
                        }
                    },
                    {
                        "asset": {
                            "type": "html",
                            "html": "<p>MAIN TEXT BLOCK</p>",
                            "css": "p { font-family: 'Open Sans'; color: #ffffff; font-size: 45px; text-align: center; }",
                            "width": 950,
                            "height": 200
                        },
                        "offset": {
                            "y": -0.1
                        },
                        "start": 10.5,
                        "length": 7,
                        "position": "center",
                        "effect": "zoomIn",
                        "transition": {
                            "in": "fade",
                            "out": "fade"
                        }
                    }
                ]
            },
            {
                "clips": [
                    {
                        "asset": {
                            "type": "html",
                            "html": "<p>LOREM IPSUM DOLOR SIT AMET, CONSECTETUR ADIPISCING ELIT</p>",
                            "css": "p { font-family: 'Open Sans'; color: #77111111; font-size: 38px; text-align: center; }",
                            "width": 950,
                            "height": 200
                        },
                        "offset": {
                            "x": 0.0025,
                            "y": -0.104
                        },
                        "start": 0.5,
                        "length": 4.5,
                        "position": "center",
                        "transition": {
                            "in": "fade",
                            "out": "fade"
                        }
                    },
                    {
                        "asset": {
                            "type": "html",
                            "html": "<p>CONSECTETUR ADIPISCING ELIT</p>",
                            "css": "p { font-family: 'Open Sans'; color: #77111111; font-size: 38px; text-align: center; }",
                            "width": 950,
                            "height": 200
                        },
                        "offset": {
                            "x": 0.0025,
                            "y": -0.104
                        },
                        "start": 5,
                        "length": 4.5,
                        "position": "center",
                        "transition": {
                            "in": "fade",
                            "out": "fade"
                        }
                    }
                ]
            },
            {
                "clips": [
                    {
                        "asset": {
                            "type": "video",
                            "src": "https://player.vimeo.com/external/439955856.hd.mp4?s=d4086b82e870e2f0b67bbb2037b3104075d898b9&profile_id=175&oauth2_token_id=57447761"
                        },
                        "start": 0,
                        "length": 10
                    },
                    {
                        "asset": {
                            "type": "video",
                            "src": "https://shotstack-ingest-api-stage-au.s3.ap-southeast-2.amazonaws.com/c9npc4w5c4/zzyb59sw-2slr-sp4v-xdzm-0v75wp4zknme/source.mp4"
                        },
                        "length": 7.5,
                        "start": 10
                    }
                ]
            }
        ]
    },
    "output": {
        "format": "mp4",
        "size": {
            "width": 1920,
            "height": 1080
        }
    }
}