H.264

Encoding.com's preferred H.264/AVC encoder is x264.

The x264 Project has led the way on H.264 development by introducing many key features. Variance Adaptive Quantization (VAQ) and Rate–Distortion Optimization (RDO) attempt to preserve video quality and motion estimation against the amount of data required to encode the video. Advanced controls include options for GOP structure, keyframing, scene detection, macroblocking, and interframe quantization. Many of these features are discussed in depth on this page. A basic job request and additional possible parameters are below and in the following sections.

<?xml version="1.0"?>
<query>
    <userid>[UserID]</userid> <!-- required-->
    <userkey>[UserKey]</userkey> <!-- required-->
    <action>[Action]</action> <!-- required-->
    <source>[SourceFile]</source> <!-- required-->
    <format>
        <output>[OutputFormat]</output> <!-- required-->
        <video_codec>libx264</video_codec>
        <video_codec_parameters>
            <keyint_min>[GOPSize]</keyint_min>
            <level>[Level]</level>
            <sc_threshold>[Threshold]</sc_threshold>
            <bf>[BFramesNumber]</bf>
            <b_strategy>[0|1|2]</b_strategy>
            <flags>[Flags]</flags>
            <coder>[0|1]</coder>
            <refs>[RefsNumber]</refs>
            <flags2>[Flags]</flags2>
            <deblockalpha>[DeblockerAlpha]</deblockalpha>
            <deblockbeta>[DeblockerBeta]</deblockbeta>
            <directpred>[0|1|2|3]</directpred>
            <aq-strength>[AQStrength]</aq-strength>
            <force-cfr>[1|0]</force-cfr>
            <cqp>[ConstantQuantizer]</cqp>
            <crf>[ConstantRatefactor]</crf>
            <qmin>[MinQuantizer]</qmin>
            <qmax>[MaxQuantizer]</qmax>
            <qdiff>[MaxQPStep]</qdiff>
            <bt>[AvgBitrateVariance]</bt>
            <i_qfactor>[IPFramesQscaleDiff]</i_qfactor>
            <b_qfactor>[IBFramesQscaleDiff]</b_qfactor>
            <chromaoffset>[ChromaLumaQPDiff]</chromaoffset>
            <pass>[1|2|3]</pass>
            <rc_eq>[RatecontrolEquation]</rc_eq>
            <qcomp>[QPCurve]</qcomp>
            <complexityblur>[ComplexityBlur]</complexityblur>
            <qblur>[QBlur]</qblur>
            <rc-lookahead>[RCLookahead]</rc-lookahead>
            <partitions>[Partitions]</partitions>
            <me_method>[MEMethod]</me_method>
            <me_range>[MERange]</me_range>
            <subq>[SubQAlgo]</subq>
            <trellis>[0|1|2]</trellis>
            <videoformat>[Format]</videoformat>
            <colorprim>[ColorPrimaries]</colorprim>
            <transfer>[TransferCharacteristics]</transfer>
            <colormatrix>[MatrixCoefficients]</colormatrix>
            <nal-hrd>[none|vbr|cbr]</nal-hrd>
            <afd>[ActiveFormatDescription]</afd>
            <hide_encoding_settings>[yes|no]</hide_encoding_settings>
            <avcintra-class>[50|100|200]</avcintra-class>
        </video_codec_parameters>
    </format>
</query>
{
    "query": {
        "userid": "[UserID]", // required
        "userkey": "[UserKey]", // required
        "action": "[Action]", // required
        "source": "[SourceFile]", // required
        "format": {
            "output": "[OutputFormat]", // required
            "video_codec": "libx264",
            "video_codec_parameters": {
                "keyint_min": "[GOPSize]",
                "level": "[Level]",
                "sc_threshold": "[Threshold]",
                "bf": "[BFramesNumber]",
                "b_strategy": "[0|1|2]",
                "flags": "[Flags]",
                "coder": "[0|1]",
                "refs": "[RefsNumber]",
                "flags2": "[Flags]",
                "deblockalpha": "[DeblockerAlpha]",
                "deblockbeta": "[DeblockerBeta]",
                "directpred": "[0|1|2|3]",
                "aq-strength": "[AQStrength]",
                "force-cfr": "[1|0]",
                "cqp": "[ConstantQuantizer]",
                "crf": "[ConstantRatefactor]",
                "qmin": "[MinQuantizer]",
                "qmax": "[MaxQuantizer]",
                "qdiff": "[MaxQPStep]",
                "bt": "[AvgBitrateVariance]",
                "i_qfactor": "[IPFramesQscaleDiff]",
                "b_qfactor": "[IBFramesQscaleDiff]",
                "chromaoffset": "[ChromaLumaQPDiff]",
                "pass": "[1|2|3]",
                "rc_eq": "[RatecontrolEquation]",
                "qcomp": "[QPCurve]",
                "complexityblur": "[ComplexityBlur]",
                "qblur": "[QBlur]",
                "rc-lookahead": "[RCLookahead]",
                "partitions": "[Partitions]",
                "me_method": "[MEMethod]",
                "me_range": "[MERange]",
                "subq": "[SubQAlgo]",
                "trellis": "[0|1|2]",
                "videoformat": "[Format]",
                "colorprim": "[ColorPrimaries]",
                "transfer": "[TransferCharacteristics]",
                "colormatrix": "[MatrixCoefficients]",
                "nal-hrd": "[none|vbr|cbr]",
                "afd": "[ActiveFormatDescription]",
                "hide_encoding_settings": "[yes|no]",
                "avcintra-class": "[50|100|200]"
            }
        }
    }
}