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/*
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 * Raw Video Codec
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 * Copyright (c) 2001 Fabrice Bellard.
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 *
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 * This library is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2 of the License, or (at your option) any later version.
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 *
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 * This library is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with this library; if not, write to the Free Software
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 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
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 */
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/**
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 * @file raw.c
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 * Raw Video Codec
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 */
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#include "avcodec.h"
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typedef struct RawVideoContext {
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    unsigned char * buffer;  /* block of memory for holding one frame */
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    unsigned char * p;       /* current position in buffer */
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    int             length;  /* number of bytes in buffer */
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    AVFrame pic;             ///< AVCodecContext.coded_frame
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} RawVideoContext;
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typedef struct PixleFormatTag {
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    int pix_fmt;
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    unsigned int fourcc;
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} PixelFormatTag;
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const PixelFormatTag pixelFormatTags[] = {
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    { PIX_FMT_YUV420P, MKTAG('I', '4', '2', '0') }, /* Planar formats */
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    { PIX_FMT_YUV420P, MKTAG('I', 'Y', 'U', 'V') },
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    { PIX_FMT_YUV410P, MKTAG('Y', 'U', 'V', '9') },
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    { PIX_FMT_YUV411P, MKTAG('Y', '4', '1', 'B') },
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    { PIX_FMT_YUV422P, MKTAG('Y', '4', '2', 'B') },
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    { PIX_FMT_GRAY8,   MKTAG('Y', '8', '0', '0') },
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    { PIX_FMT_GRAY8,   MKTAG(' ', ' ', 'Y', '8') },
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    { PIX_FMT_YUV422,  MKTAG('Y', '4', '2', '2') }, /* Packed formats */
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    { PIX_FMT_YUV422,  MKTAG('U', 'Y', 'V', 'Y') },
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    { PIX_FMT_GRAY8,   MKTAG('G', 'R', 'E', 'Y') },
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    { -1, 0 },
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};
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static int findPixelFormat(unsigned int fourcc)
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{
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    const PixelFormatTag * tags = pixelFormatTags;
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    while (tags->pix_fmt >= 0) {
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        if (tags->fourcc == fourcc)
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            return tags->pix_fmt;
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        tags++;
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    }
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    return PIX_FMT_YUV420P;
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}
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static unsigned int findFourCC(int fmt)
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{
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    const PixelFormatTag * tags = pixelFormatTags;
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    while (tags->pix_fmt >= 0) {
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        if (tags->pix_fmt == fmt)
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            return tags->fourcc;
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        tags++; 
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    }
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    return 0;
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}
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/* RAW Decoder Implementation */
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static int raw_init_decoder(AVCodecContext *avctx)
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{
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    RawVideoContext *context = avctx->priv_data;
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    if (avctx->codec_tag)
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        avctx->pix_fmt = findPixelFormat(avctx->codec_tag);
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    context->length = avpicture_get_size(avctx->pix_fmt, avctx->width, avctx->height);
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    context->buffer = av_malloc(context->length);
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    context->p      = context->buffer;
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    context->pic.pict_type = FF_I_TYPE;
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    context->pic.key_frame = 1;
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    avctx->coded_frame= &context->pic;
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    if (!context->buffer)
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        return -1;
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    return 0;
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}
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static int raw_decode(AVCodecContext *avctx,
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                            void *data, int *data_size,
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                            uint8_t *buf, int buf_size)
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{
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    RawVideoContext *context = avctx->priv_data;
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    int bytesNeeded;
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    AVPicture * picture = (AVPicture *) data;
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    /* Early out without copy if packet size == frame size */
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    if (buf_size == context->length  &&  context->p == context->buffer) {
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        avpicture_fill(picture, buf, avctx->pix_fmt, avctx->width, avctx->height);
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        *data_size = sizeof(AVPicture);
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        return buf_size;
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    }
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    bytesNeeded = context->length - (context->p - context->buffer);
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    if (buf_size < bytesNeeded) {
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        memcpy(context->p, buf, buf_size);
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        context->p += buf_size;
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        *data_size = 0;
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        return buf_size;
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    }
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    memcpy(context->p, buf, bytesNeeded);
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    context->p = context->buffer;
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    avpicture_fill(picture, context->buffer, avctx->pix_fmt, avctx->width, avctx->height);
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    *data_size = sizeof(AVPicture);
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    return bytesNeeded;
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}
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static int raw_close_decoder(AVCodecContext *avctx)
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{
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    RawVideoContext *context = avctx->priv_data;
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    av_freep(&context->buffer);
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    return 0;
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}
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/* RAW Encoder Implementation */
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static int raw_init_encoder(AVCodecContext *avctx)
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{
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    avctx->coded_frame = (AVFrame *)avctx->priv_data;
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    avctx->coded_frame->pict_type = FF_I_TYPE;
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    avctx->coded_frame->key_frame = 1;
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    avctx->codec_tag = findFourCC(avctx->pix_fmt);
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    return 0;
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}
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static int raw_encode(AVCodecContext *avctx,
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                            unsigned char *frame, int buf_size, void *data)
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{
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    return avpicture_layout((AVPicture *)data, avctx->pix_fmt, avctx->width,
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                                               avctx->height, frame, buf_size);
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}
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AVCodec rawvideo_encoder = {
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    "rawvideo",
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    CODEC_TYPE_VIDEO,
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    CODEC_ID_RAWVIDEO,
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    sizeof(AVFrame),
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    raw_init_encoder,
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    raw_encode,
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};
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AVCodec rawvideo_decoder = {
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    "rawvideo",
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    CODEC_TYPE_VIDEO,
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    CODEC_ID_RAWVIDEO,
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    sizeof(RawVideoContext),
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    raw_init_decoder,
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    NULL,
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    raw_close_decoder,
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    raw_decode,
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};