FFmpeg/libavcodec/libaomenc.c

/*
 * Copyright (c) 2010, Google, Inc.
 *
 * This file is part of Libav.
 *
 * Libav is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * Libav is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with Libav; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#define AOM_DISABLE_CTRL_TYPECHECKS 1
#include <aom/aom_encoder.h>
#include <aom/aomcx.h>

#include "libavutil/base64.h"
#include "libavutil/common.h"
#include "libavutil/mathematics.h"
#include "libavutil/opt.h"
#include "libavutil/pixdesc.h"

#include "avcodec.h"
#include "internal.h"
#include "libaom.h"

/*
 * Portion of struct aom_codec_cx_pkt from aom_encoder.h.
 * One encoded frame returned from the library.
 */
struct FrameListData {
    void *buf;                       /* compressed data buffer */
    size_t sz;                       /* length of compressed data */
    int64_t pts;                     /* time stamp to show frame
                                      * (in timebase units) */
    unsigned long duration;          /* duration to show frame
                                      * (in timebase units) */
    uint32_t flags;                  /* flags for this frame */
    struct FrameListData *next;
};

typedef struct AOMEncoderContext {
    AVClass *class;
    struct aom_codec_ctx encoder;
    struct aom_image rawimg;
    struct aom_fixed_buf twopass_stats;
    struct FrameListData *coded_frame_list;
    int cpu_used;
    int auto_alt_ref;
    int lag_in_frames;
    int error_resilient;
    int crf;
    int static_thresh;
    int drop_threshold;
    int noise_sensitivity;
} AOMContext;

static const char *const ctlidstr[] = {
    [AOME_SET_CPUUSED]          = "AOME_SET_CPUUSED",
    [AOME_SET_CQ_LEVEL]         = "AOME_SET_CQ_LEVEL",
    [AOME_SET_ENABLEAUTOALTREF] = "AOME_SET_ENABLEAUTOALTREF",
    [AOME_SET_STATIC_THRESHOLD] = "AOME_SET_STATIC_THRESHOLD",
};

static av_cold void log_encoder_error(AVCodecContext *avctx, const char *desc)
{
    AOMContext *ctx    = avctx->priv_data;
    const char *error  = aom_codec_error(&ctx->encoder);
    const char *detail = aom_codec_error_detail(&ctx->encoder);

    av_log(avctx, AV_LOG_ERROR, "%s: %s\n", desc, error);
    if (detail)
        av_log(avctx, AV_LOG_ERROR, "  Additional information: %s\n", detail);
}

static av_cold void dump_enc_cfg(AVCodecContext *avctx,
                                 const struct aom_codec_enc_cfg *cfg)
{
    int width = -30;
    int level = AV_LOG_DEBUG;

    av_log(avctx, level, "aom_codec_enc_cfg\n");
    av_log(avctx, level, "generic settings\n"
                         "  %*s%u\n  %*s%u\n  %*s%u\n  %*s%u\n  %*s%u\n"
                         "  %*s{%u/%u}\n  %*s%u\n  %*s%d\n  %*s%u\n",
           width, "g_usage:", cfg->g_usage,
           width, "g_threads:", cfg->g_threads,
           width, "g_profile:", cfg->g_profile,
           width, "g_w:", cfg->g_w,
           width, "g_h:", cfg->g_h,
           width, "g_timebase:", cfg->g_timebase.num, cfg->g_timebase.den,
           width, "g_error_resilient:", cfg->g_error_resilient,
           width, "g_pass:", cfg->g_pass,
           width, "g_lag_in_frames:", cfg->g_lag_in_frames);
    av_log(avctx, level, "rate control settings\n"
                         "  %*s%u\n  %*s%d\n  %*s%p(%zu)\n  %*s%u\n",
           width, "rc_dropframe_thresh:", cfg->rc_dropframe_thresh,
           width, "rc_end_usage:", cfg->rc_end_usage,
           width, "rc_twopass_stats_in:", cfg->rc_twopass_stats_in.buf, cfg->rc_twopass_stats_in.sz,
           width, "rc_target_bitrate:", cfg->rc_target_bitrate);
    av_log(avctx, level, "quantizer settings\n"
                         "  %*s%u\n  %*s%u\n",
           width, "rc_min_quantizer:", cfg->rc_min_quantizer,
           width, "rc_max_quantizer:", cfg->rc_max_quantizer);
    av_log(avctx, level, "bitrate tolerance\n"
                         "  %*s%u\n  %*s%u\n",
           width, "rc_undershoot_pct:", cfg->rc_undershoot_pct,
           width, "rc_overshoot_pct:", cfg->rc_overshoot_pct);
    av_log(avctx, level, "decoder buffer model\n"
                         "  %*s%u\n  %*s%u\n  %*s%u\n",
           width, "rc_buf_sz:", cfg->rc_buf_sz,
           width, "rc_buf_initial_sz:", cfg->rc_buf_initial_sz,
           width, "rc_buf_optimal_sz:", cfg->rc_buf_optimal_sz);
    av_log(avctx, level, "2 pass rate control settings\n"
                         "  %*s%u\n  %*s%u\n  %*s%u\n",
           width, "rc_2pass_vbr_bias_pct:", cfg->rc_2pass_vbr_bias_pct,
           width, "rc_2pass_vbr_minsection_pct:", cfg->rc_2pass_vbr_minsection_pct,
           width, "rc_2pass_vbr_maxsection_pct:", cfg->rc_2pass_vbr_maxsection_pct);
    av_log(avctx, level, "keyframing settings\n"
                         "  %*s%d\n  %*s%u\n  %*s%u\n",
           width, "kf_mode:", cfg->kf_mode,
           width, "kf_min_dist:", cfg->kf_min_dist,
           width, "kf_max_dist:", cfg->kf_max_dist);
    av_log(avctx, level, "\n");
}

static void coded_frame_add(void *list, struct FrameListData *cx_frame)
{
    struct FrameListData **p = list;

    while (*p)
        p = &(*p)->next;
    *p = cx_frame;
    cx_frame->next = NULL;
}

static av_cold void free_coded_frame(struct FrameListData *cx_frame)
{
    av_freep(&cx_frame->buf);
    av_freep(&cx_frame);
}

static av_cold void free_frame_list(struct FrameListData *list)
{
    struct FrameListData *p = list;

    while (p) {
        list = list->next;
        free_coded_frame(p);
        p = list;
    }
}

static av_cold int codecctl_int(AVCodecContext *avctx,
                                enum aome_enc_control_id id, int val)
{
    AOMContext *ctx = avctx->priv_data;
    char buf[80];
    int width = -30;
    int res;

    snprintf(buf, sizeof(buf), "%s:", ctlidstr[id]);
    av_log(avctx, AV_LOG_DEBUG, "  %*s%d\n", width, buf, val);

    res = aom_codec_control(&ctx->encoder, id, val);
    if (res != AOM_CODEC_OK) {
        snprintf(buf, sizeof(buf), "Failed to set %s codec control",
                 ctlidstr[id]);
        log_encoder_error(avctx, buf);
        return AVERROR(EINVAL);
    }

    return 0;
}

static av_cold int aom_free(AVCodecContext *avctx)
{
    AOMContext *ctx = avctx->priv_data;

    aom_codec_destroy(&ctx->encoder);
    av_freep(&ctx->twopass_stats.buf);
    av_freep(&avctx->stats_out);
    free_frame_list(ctx->coded_frame_list);
    return 0;
}

static av_cold int aom_init(AVCodecContext *avctx)
{
    AOMContext *ctx = avctx->priv_data;
    struct aom_codec_enc_cfg enccfg = { 0 };
    AVCPBProperties *cpb_props;
    int res;
    const struct aom_codec_iface *iface = &aom_codec_av1_cx_algo;

    av_log(avctx, AV_LOG_INFO, "%s\n", aom_codec_version_str());
    av_log(avctx, AV_LOG_VERBOSE, "%s\n", aom_codec_build_config());

    if ((res = aom_codec_enc_config_default(iface, &enccfg, 0)) != AOM_CODEC_OK) {
        av_log(avctx, AV_LOG_ERROR, "Failed to get config: %s\n",
               aom_codec_err_to_string(res));
        return AVERROR(EINVAL);
    }
    dump_enc_cfg(avctx, &enccfg);

    enccfg.g_w            = avctx->width;
    enccfg.g_h            = avctx->height;
    enccfg.g_timebase.num = avctx->time_base.num;
    enccfg.g_timebase.den = avctx->time_base.den;
    enccfg.g_threads      = avctx->thread_count;

    if (ctx->lag_in_frames >= 0)
        enccfg.g_lag_in_frames = ctx->lag_in_frames;

    if (avctx->flags & AV_CODEC_FLAG_PASS1)
        enccfg.g_pass = AOM_RC_FIRST_PASS;
    else if (avctx->flags & AV_CODEC_FLAG_PASS2)
        enccfg.g_pass = AOM_RC_LAST_PASS;
    else
        enccfg.g_pass = AOM_RC_ONE_PASS;

    if (!avctx->bit_rate)
        avctx->bit_rate = enccfg.rc_target_bitrate * 1000;
    else
        enccfg.rc_target_bitrate = av_rescale_rnd(avctx->bit_rate, 1, 1000,
                                                  AV_ROUND_NEAR_INF);

    if (ctx->crf)
        enccfg.rc_end_usage = AOM_CQ;
    else if (avctx->rc_min_rate == avctx->rc_max_rate &&
             avctx->rc_min_rate == avctx->bit_rate)
        enccfg.rc_end_usage = AOM_CBR;

    if (avctx->qmin > 0)
        enccfg.rc_min_quantizer = avctx->qmin;
    if (avctx->qmax > 0)
        enccfg.rc_max_quantizer = avctx->qmax;

    enccfg.rc_dropframe_thresh = ctx->drop_threshold;

    // 0-100 (0 => CBR, 100 => VBR)
    enccfg.rc_2pass_vbr_bias_pct       = round(avctx->qcompress * 100);
    enccfg.rc_2pass_vbr_minsection_pct =
        avctx->rc_min_rate * 100LL / avctx->bit_rate;
    if (avctx->rc_max_rate)
        enccfg.rc_2pass_vbr_maxsection_pct =
            avctx->rc_max_rate * 100LL / avctx->bit_rate;

    if (avctx->rc_buffer_size)
        enccfg.rc_buf_sz =
            avctx->rc_buffer_size * 1000LL / avctx->bit_rate;
    if (avctx->rc_initial_buffer_occupancy)
        enccfg.rc_buf_initial_sz =
            avctx->rc_initial_buffer_occupancy * 1000LL / avctx->bit_rate;
    enccfg.rc_buf_optimal_sz = enccfg.rc_buf_sz * 5 / 6;

    // _enc_init() will balk if kf_min_dist differs from max w/AOM_KF_AUTO
    if (avctx->keyint_min >= 0 && avctx->keyint_min == avctx->gop_size)
        enccfg.kf_min_dist = avctx->keyint_min;
    if (avctx->gop_size >= 0)
        enccfg.kf_max_dist = avctx->gop_size;

    if (enccfg.g_pass == AOM_RC_FIRST_PASS)
        enccfg.g_lag_in_frames = 0;
    else if (enccfg.g_pass == AOM_RC_LAST_PASS) {
        int decode_size, ret;

        if (!avctx->stats_in) {
            av_log(avctx, AV_LOG_ERROR, "No stats file for second pass\n");
            return AVERROR_INVALIDDATA;
        }

        ctx->twopass_stats.sz = strlen(avctx->stats_in) * 3 / 4;
        ret                   = av_reallocp(&ctx->twopass_stats.buf, ctx->twopass_stats.sz);
        if (ret < 0) {
            av_log(avctx, AV_LOG_ERROR,
                   "Stat buffer alloc (%zu bytes) failed\n",
                   ctx->twopass_stats.sz);
            return ret;
        }
        decode_size = av_base64_decode(ctx->twopass_stats.buf, avctx->stats_in,
                                       ctx->twopass_stats.sz);
        if (decode_size < 0) {
            av_log(avctx, AV_LOG_ERROR, "Stat buffer decode failed\n");
            return AVERROR_INVALIDDATA;
        }

        ctx->twopass_stats.sz      = decode_size;
        enccfg.rc_twopass_stats_in = ctx->twopass_stats;
    }

    /* 0-3: For non-zero values the encoder increasingly optimizes for reduced
     * complexity playback on low powered devices at the expense of encode
     * quality. */
    if (avctx->profile != FF_PROFILE_UNKNOWN)
        enccfg.g_profile = avctx->profile;
    else if (avctx->pix_fmt == AV_PIX_FMT_YUV420P ||
             avctx->pix_fmt == AV_PIX_FMT_YUV420P10)
        avctx->profile = enccfg.g_profile = FF_PROFILE_AV1_MAIN;
    else if (avctx->pix_fmt == AV_PIX_FMT_YUV444P ||
             avctx->pix_fmt == AV_PIX_FMT_YUV444P10)
        avctx->profile = enccfg.g_profile = FF_PROFILE_AV1_HIGH;
    else {
        avctx->profile = enccfg.g_profile = FF_PROFILE_AV1_PROFESSIONAL;
    }


    enccfg.g_error_resilient = ctx->error_resilient;

    dump_enc_cfg(avctx, &enccfg);
    /* Construct Encoder Context */
    res = aom_codec_enc_init(&ctx->encoder, iface, &enccfg, 0);
    if (res != AOM_CODEC_OK) {
        log_encoder_error(avctx, "Failed to initialize encoder");
        return AVERROR(EINVAL);
    }

    // codec control failures are currently treated only as warnings
    av_log(avctx, AV_LOG_DEBUG, "aom_codec_control\n");
    if (ctx->cpu_used != INT_MIN)
        codecctl_int(avctx, AOME_SET_CPUUSED, ctx->cpu_used);
    if (ctx->auto_alt_ref >= 0)
        codecctl_int(avctx, AOME_SET_ENABLEAUTOALTREF, ctx->auto_alt_ref);

    codecctl_int(avctx, AOME_SET_STATIC_THRESHOLD, ctx->static_thresh);
    codecctl_int(avctx, AOME_SET_CQ_LEVEL, ctx->crf);

    // provide dummy value to initialize wrapper, values will be updated each _encode()
    aom_img_wrap(&ctx->rawimg, ff_aom_pixfmt_to_imgfmt(avctx->pix_fmt),
                 avctx->width, avctx->height, 1, (unsigned char *)1);

    cpb_props = ff_add_cpb_side_data(avctx);
    if (!cpb_props)
        return AVERROR(ENOMEM);

    if (enccfg.rc_end_usage == AOM_CBR ||
        enccfg.g_pass != AOM_RC_ONE_PASS) {
        cpb_props->max_bitrate = avctx->rc_max_rate;
        cpb_props->min_bitrate = avctx->rc_min_rate;
        cpb_props->avg_bitrate = avctx->bit_rate;
    }
    cpb_props->buffer_size = avctx->rc_buffer_size;

    return 0;
}

static inline void cx_pktcpy(struct FrameListData *dst,
                             const struct aom_codec_cx_pkt *src)
{
    dst->pts      = src->data.frame.pts;
    dst->duration = src->data.frame.duration;
    dst->flags    = src->data.frame.flags;
    dst->sz       = src->data.frame.sz;
    dst->buf      = src->data.frame.buf;
}

/**
 * Store coded frame information in format suitable for return from encode2().
 *
 * Write information from @a cx_frame to @a pkt
 * @return packet data size on success
 * @return a negative AVERROR on error
 */
static int storeframe(AVCodecContext *avctx, struct FrameListData *cx_frame,
                      AVPacket *pkt)
{
    int ret = ff_alloc_packet(pkt, cx_frame->sz);
    if (ret < 0) {
        av_log(avctx, AV_LOG_ERROR,
               "Error getting output packet of size %zu.\n", cx_frame->sz);
        return ret;
    }
    memcpy(pkt->data, cx_frame->buf, pkt->size);
    pkt->pts = pkt->dts = cx_frame->pts;

    if (!!(cx_frame->flags & AOM_FRAME_IS_KEY))
        pkt->flags |= AV_PKT_FLAG_KEY;
    return pkt->size;
}

/**
 * Queue multiple output frames from the encoder, returning the front-most.
 * In cases where aom_codec_get_cx_data() returns more than 1 frame append
 * the frame queue. Return the head frame if available.
 * @return Stored frame size
 * @return AVERROR(EINVAL) on output size error
 * @return AVERROR(ENOMEM) on coded frame queue data allocation error
 */
static int queue_frames(AVCodecContext *avctx, AVPacket *pkt_out)
{
    AOMContext *ctx = avctx->priv_data;
    const struct aom_codec_cx_pkt *pkt;
    const void *iter = NULL;
    int size = 0;

    if (ctx->coded_frame_list) {
        struct FrameListData *cx_frame = ctx->coded_frame_list;
        /* return the leading frame if we've already begun queueing */
        size = storeframe(avctx, cx_frame, pkt_out);
        if (size < 0)
            return size;
        ctx->coded_frame_list = cx_frame->next;
        free_coded_frame(cx_frame);
    }

    /* consume all available output from the encoder before returning. buffers
     * are only good through the next aom_codec call */
    while ((pkt = aom_codec_get_cx_data(&ctx->encoder, &iter))) {
        switch (pkt->kind) {
        case AOM_CODEC_CX_FRAME_PKT:
            if (!size) {
                struct FrameListData cx_frame;

                /* avoid storing the frame when the list is empty and we haven't yet
                 * provided a frame for output */
                assert(!ctx->coded_frame_list);
                cx_pktcpy(&cx_frame, pkt);
                size = storeframe(avctx, &cx_frame, pkt_out);
                if (size < 0)
                    return size;
            } else {
                struct FrameListData *cx_frame =
                    av_malloc(sizeof(struct FrameListData));

                if (!cx_frame) {
                    av_log(avctx, AV_LOG_ERROR,
                           "Frame queue element alloc failed\n");
                    return AVERROR(ENOMEM);
                }
                cx_pktcpy(cx_frame, pkt);
                cx_frame->buf = av_malloc(cx_frame->sz);

                if (!cx_frame->buf) {
                    av_log(avctx, AV_LOG_ERROR,
                           "Data buffer alloc (%zu bytes) failed\n",
                           cx_frame->sz);
                    av_freep(&cx_frame);
                    return AVERROR(ENOMEM);
                }
                memcpy(cx_frame->buf, pkt->data.frame.buf, pkt->data.frame.sz);
                coded_frame_add(&ctx->coded_frame_list, cx_frame);
            }
            break;
        case AOM_CODEC_STATS_PKT:
        {
            struct aom_fixed_buf *stats = &ctx->twopass_stats;
            int err;
            if ((err = av_reallocp(&stats->buf,
                                   stats->sz +
                                   pkt->data.twopass_stats.sz)) < 0) {
                stats->sz = 0;
                av_log(avctx, AV_LOG_ERROR, "Stat buffer realloc failed\n");
                return err;
            }
            memcpy((uint8_t *)stats->buf + stats->sz,
                   pkt->data.twopass_stats.buf, pkt->data.twopass_stats.sz);
            stats->sz += pkt->data.twopass_stats.sz;
            break;
        }
        case AOM_CODEC_PSNR_PKT: // FIXME add support for AV_CODEC_FLAG_PSNR
        case AOM_CODEC_CUSTOM_PKT:
            // ignore unsupported/unrecognized packet types
            break;
        }
    }

    return size;
}

static int aom_encode(AVCodecContext *avctx, AVPacket *pkt,
                      const AVFrame *frame, int *got_packet)
{
    AOMContext *ctx = avctx->priv_data;
    struct aom_image *rawimg = NULL;
    int64_t timestamp = 0;
    int res, coded_size;
    aom_enc_frame_flags_t flags = 0;

    if (frame) {
        rawimg                      = &ctx->rawimg;
        rawimg->planes[AOM_PLANE_Y] = frame->data[0];
        rawimg->planes[AOM_PLANE_U] = frame->data[1];
        rawimg->planes[AOM_PLANE_V] = frame->data[2];
        rawimg->stride[AOM_PLANE_Y] = frame->linesize[0];
        rawimg->stride[AOM_PLANE_U] = frame->linesize[1];
        rawimg->stride[AOM_PLANE_V] = frame->linesize[2];
        timestamp                   = frame->pts;
        switch (frame->color_range) {
        case AVCOL_RANGE_MPEG:
            rawimg->range = AOM_CR_STUDIO_RANGE;
            break;
        case AVCOL_RANGE_JPEG:
            rawimg->range = AOM_CR_FULL_RANGE;
            break;
        }

        if (frame->pict_type == AV_PICTURE_TYPE_I)
            flags |= AOM_EFLAG_FORCE_KF;
    }

    res = aom_codec_encode(&ctx->encoder, rawimg, timestamp,
                           avctx->ticks_per_frame, flags);
    if (res != AOM_CODEC_OK) {
        log_encoder_error(avctx, "Error encoding frame");
        return AVERROR_INVALIDDATA;
    }
    coded_size = queue_frames(avctx, pkt);

    if (!frame && avctx->flags & AV_CODEC_FLAG_PASS1) {
        size_t b64_size = AV_BASE64_SIZE(ctx->twopass_stats.sz);

        avctx->stats_out = av_malloc(b64_size);
        if (!avctx->stats_out) {
            av_log(avctx, AV_LOG_ERROR, "Stat buffer alloc (%zu bytes) failed\n",
                   b64_size);
            return AVERROR(ENOMEM);
        }
        av_base64_encode(avctx->stats_out, b64_size, ctx->twopass_stats.buf,
                         ctx->twopass_stats.sz);
    }

    *got_packet = !!coded_size;
    return 0;
}

#define OFFSET(x) offsetof(AOMContext, x)
#define VE AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
static const AVOption options[] = {
    { "cpu-used",        "Quality/Speed ratio modifier",           OFFSET(cpu_used),        AV_OPT_TYPE_INT, {.i64 = 1}, INT_MIN, INT_MAX, VE},
    { "auto-alt-ref",    "Enable use of alternate reference "
                         "frames (2-pass only)",                   OFFSET(auto_alt_ref),    AV_OPT_TYPE_INT, {.i64 = -1},      -1,      1,       VE},
    { "lag-in-frames",   "Number of frames to look ahead at for "
                         "alternate reference frame selection",    OFFSET(lag_in_frames),   AV_OPT_TYPE_INT, {.i64 = -1},      -1,      INT_MAX, VE},
    { "error-resilience", "Error resilience configuration", OFFSET(error_resilient), AV_OPT_TYPE_FLAGS, {.i64 = 0}, INT_MIN, INT_MAX, VE, "er"},
    { "default",         "Improve resiliency against losses of whole frames", 0, AV_OPT_TYPE_CONST, {.i64 = AOM_ERROR_RESILIENT_DEFAULT}, 0, 0, VE, "er"},
    { "crf",              "Select the quality for constant quality mode", offsetof(AOMContext, crf), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 63, VE },
    { "static-thresh",    "A change threshold on blocks below which they will be skipped by the encoder", OFFSET(static_thresh), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, VE },
    { "drop-threshold",   "Frame drop threshold", offsetof(AOMContext, drop_threshold), AV_OPT_TYPE_INT, {.i64 = 0 }, INT_MIN, INT_MAX, VE },
    { "noise-sensitivity", "Noise sensitivity", OFFSET(noise_sensitivity), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 4, VE},
    { NULL }
};

static const AVCodecDefault defaults[] = {
    { "qmin",             "-1" },
    { "qmax",             "-1" },
    { "g",                "-1" },
    { "keyint_min",       "-1" },
    { NULL },
};

static const AVClass class_aom = {
    .class_name = "libaom encoder",
    .item_name  = av_default_item_name,
    .option     = options,
    .version    = LIBAVUTIL_VERSION_INT,
};

AVCodec ff_libaom_av1_encoder = {
    .name           = "libaom-av1",
    .long_name      = NULL_IF_CONFIG_SMALL("libaom AV1"),
    .type           = AVMEDIA_TYPE_VIDEO,
    .id             = AV_CODEC_ID_AV1,
    .priv_data_size = sizeof(AOMContext),
    .init           = aom_init,
    .encode2        = aom_encode,
    .close          = aom_free,
    .capabilities   = AV_CODEC_CAP_DELAY | AV_CODEC_CAP_AUTO_THREADS | AV_CODEC_CAP_EXPERIMENTAL,
    .pix_fmts       = (const enum AVPixelFormat[]){ AV_PIX_FMT_YUV420P, AV_PIX_FMT_NONE },
    .priv_class     = &class_aom,
    .defaults       = defaults,
    .wrapper_name   = "libaom",
};