[FFmpeg-devel] [PATCH] VP8 de/encode via libvpx

[Stefano Sabatini]

On date Wednesday 2010-05-19 19:57:13 -0400, James Zern encoded:
[...]
> Index: libavcodec/libvpxdec.c
> ===================================================================
> --- libavcodec/libvpxdec.c	(revision 0)
> +++ libavcodec/libvpxdec.c	(revision 0)
> @@ -0,0 +1,127 @@
> +/*
> + * Copyright (c) 2010, Google, Inc.
> + *
> + * This file is part of FFmpeg.
> + *
> + * FFmpeg 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.
> + *
> + * FFmpeg 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 FFmpeg; if not, write to the Free Software
> + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
> + */
> +
> +/**
> + * @file
> + * @brief VP8 decoder support via libvpx

The @brief is not required.

> + */
> +
> +#define VPX_CODEC_DISABLE_COMPAT 1
> +#include <vpx_decoder.h>
> +#include <vp8dx.h>
> +
> +#include "avcodec.h"
> +
> +typedef struct VP8DecoderContext {
> +    vpx_codec_ctx_t decoder;
> +} VP8Context;
> +
> +static av_cold int vp8_init(AVCodecContext *avctx)
> +{
> +    VP8Context *ctx = avctx->priv_data;
> +    vpx_codec_iface_t *iface = &vpx_codec_vp8_dx_algo;
> +    vpx_codec_dec_cfg_t deccfg = { /*token partitions+1 would be a decent choice */
> +        .threads = FFMIN(avctx->thread_count, 16)
> +    };
> +
> +    av_log(avctx, AV_LOG_INFO, "%s\n", vpx_codec_version_str());
> +    av_log(avctx, AV_LOG_VERBOSE, "%s\n", vpx_codec_build_config());
> +
> +    if (vpx_codec_dec_init(&ctx->decoder, iface, &deccfg, 0) != VPX_CODEC_OK) {
> +        const char *error = vpx_codec_error(&ctx->decoder);
> +        av_log(avctx, AV_LOG_ERROR, "Failed to initialize decoder: %s\n",
> +               error);
> +        return -1;

AVERROR(EINVAL);

 +    }
> +
> +    avctx->pix_fmt = PIX_FMT_YUV420P;
> +    return 0;
> +}
> +
> +static int vp8_decode(AVCodecContext *avctx,
> +                      void *data, int *data_size, AVPacket *avpkt)
> +{
> +    VP8Context *ctx = avctx->priv_data;
> +    AVFrame *picture = data;
> +    vpx_codec_iter_t iter = NULL;
> +    vpx_image_t *img;
> +
> +    /*end of stream, vp8 does no buffering */
> +    if (avpkt->size == 0)
> +        return 0;
> +
> +    if (vpx_codec_decode(&ctx->decoder, avpkt->data, avpkt->size, NULL, 0) !=
> +        VPX_CODEC_OK) {
> +        const char *error = vpx_codec_error(&ctx->decoder);
> +        const char *detail = vpx_codec_error_detail(&ctx->decoder);
> +
> +        av_log(avctx, AV_LOG_ERROR, "Failed to decode frame: %s\n", error);
> +        if (detail)
> +            av_log(avctx, AV_LOG_ERROR, "  Additional information: %s\n",
> +                   detail);
> +        return -1;

AVERROR_INVALIDDATA

> +    }
> +
> +    if ((img = vpx_codec_get_frame(&ctx->decoder, &iter))) {
> +        if (img->fmt != IMG_FMT_I420) {
> +            av_log(avctx, AV_LOG_ERROR, "Unsupported output colorspace (%d)\n",
> +                   img->fmt);
> +            return -1;

This may be bot AVERROR_INVALIDDATA or PATCHWELCOME if the standard
define its support but it's not yet implemented.

> +        }
> +
> +        if ((int) img->d_w != avctx->width || (int) img->d_h != avctx->height) {
> +            av_log(avctx, AV_LOG_INFO, "dimension change! %dx%d -> %dx%d\n",
> +                   avctx->width, avctx->height, img->d_w, img->d_h);
> +            if (avcodec_check_dimensions(avctx, img->d_w, img->d_h))
> +                return -1;

AVERROR_INVALIDDATA

> +            avcodec_set_dimensions(avctx, img->d_w, img->d_h);
> +        }
> +        picture->data[0]     = img->planes[0];
> +        picture->data[1]     = img->planes[1];
> +        picture->data[2]     = img->planes[2];
> +        picture->data[3]     = NULL;
> +        picture->linesize[0] = img->stride[0];
> +        picture->linesize[1] = img->stride[1];
> +        picture->linesize[2] = img->stride[2];
> +        picture->linesize[3] = 0;
> +        *data_size           = sizeof(AVPicture);
> +    }
> +    return avpkt->size;
> +}
> +
> +static av_cold int vp8_free(AVCodecContext *avctx)
> +{
> +    VP8Context *ctx = avctx->priv_data;
> +    vpx_codec_destroy(&ctx->decoder);
> +    return 0;
> +}
> +
> +AVCodec libvpx_vp8_decoder = {
> +    "libvpx_vp8",
> +    AVMEDIA_TYPE_VIDEO,
> +    CODEC_ID_VP8,
> +    sizeof(VP8Context),
> +    vp8_init,
> +    NULL, /*encode */
> +    vp8_free,
> +    vp8_decode,
> +    0, /*capabilities */
> +    .long_name = NULL_IF_CONFIG_SMALL("libvpx VP8"),
> +};

-- 
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