libavcodec/cyuv.c - third_party/ffmpeg - Git at Google

 /*
  * Creative YUV (CYUV) Video Decoder
  *   by Mike Melanson (melanson@pcisys.net)
  * based on "Creative YUV (CYUV) stream format for AVI":
  *   http://www.csse.monash.edu.au/~timf/videocodec/cyuv.txt
  *
  * Copyright (C) 2003 The FFmpeg project
  *
  * 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
  * Creative YUV (CYUV) Video Decoder.
  */

 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>

 #include "avcodec.h"
 #include "internal.h"
 #include "libavutil/internal.h"


 typedef struct CyuvDecodeContext {
     AVCodecContext *avctx;
     int width, height;
 } CyuvDecodeContext;

 static av_cold int cyuv_decode_init(AVCodecContext *avctx)
 {
     CyuvDecodeContext *s = avctx->priv_data;

     s->avctx = avctx;
     s->width = avctx->width;
     /* width needs to be divisible by 4 for this codec to work */
     if (s->width & 0x3)
         return AVERROR_INVALIDDATA;
     s->height = avctx->height;

     return 0;
 }

 static int cyuv_decode_frame(AVCodecContext *avctx,
                              void *data, int *got_frame,
                              AVPacket *avpkt)
 {
     const uint8_t *buf = avpkt->data;
     int buf_size = avpkt->size;
     CyuvDecodeContext *s=avctx->priv_data;
     AVFrame *frame = data;

     unsigned char *y_plane;
     unsigned char *u_plane;
     unsigned char *v_plane;
     int y_ptr;
     int u_ptr;
     int v_ptr;

     /* prediction error tables (make it clear that they are signed values) */
     const signed char *y_table = (const signed char*)buf +  0;
     const signed char *u_table = (const signed char*)buf + 16;
     const signed char *v_table = (const signed char*)buf + 32;

     unsigned char y_pred, u_pred, v_pred;
     int stream_ptr;
     unsigned char cur_byte;
     int pixel_groups;
     int rawsize = s->height * FFALIGN(s->width,2) * 2;
     int ret;

     if (avctx->codec_id == AV_CODEC_ID_AURA) {
         y_table = u_table;
         u_table = v_table;
     }
     /* sanity check the buffer size: A buffer has 3x16-bytes tables
      * followed by (height) lines each with 3 bytes to represent groups
      * of 4 pixels. Thus, the total size of the buffer ought to be:
      *    (3 * 16) + height * (width * 3 / 4) */
     if (buf_size == 48 + s->height * (s->width * 3 / 4)) {
         avctx->pix_fmt = AV_PIX_FMT_YUV411P;
     } else if(buf_size == rawsize ) {
         avctx->pix_fmt = AV_PIX_FMT_UYVY422;
     } else {
         av_log(avctx, AV_LOG_ERROR, "got a buffer with %d bytes when %d were expected\n",
                buf_size, 48 + s->height * (s->width * 3 / 4));
         return AVERROR_INVALIDDATA;
     }

     /* pixel data starts 48 bytes in, after 3x16-byte tables */
     stream_ptr = 48;

     if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
         return ret;

     y_plane = frame->data[0];
     u_plane = frame->data[1];
     v_plane = frame->data[2];

     if (buf_size == rawsize) {
         int linesize = FFALIGN(s->width,2) * 2;
         y_plane += frame->linesize[0] * s->height;
         for (stream_ptr = 0; stream_ptr < rawsize; stream_ptr += linesize) {
             y_plane -= frame->linesize[0];
             memcpy(y_plane, buf+stream_ptr, linesize);
         }
     } else {

     /* iterate through each line in the height */
     for (y_ptr = 0, u_ptr = 0, v_ptr = 0;
          y_ptr < (s->height * frame->linesize[0]);
          y_ptr += frame->linesize[0] - s->width,
          u_ptr += frame->linesize[1] - s->width / 4,
          v_ptr += frame->linesize[2] - s->width / 4) {

         /* reset predictors */
         cur_byte = buf[stream_ptr++];
         u_plane[u_ptr++] = u_pred = cur_byte & 0xF0;
         y_plane[y_ptr++] = y_pred = (cur_byte & 0x0F) << 4;

         cur_byte = buf[stream_ptr++];
         v_plane[v_ptr++] = v_pred = cur_byte & 0xF0;
         y_pred += y_table[cur_byte & 0x0F];
         y_plane[y_ptr++] = y_pred;

         cur_byte = buf[stream_ptr++];
         y_pred += y_table[cur_byte & 0x0F];
         y_plane[y_ptr++] = y_pred;
         y_pred += y_table[(cur_byte & 0xF0) >> 4];
         y_plane[y_ptr++] = y_pred;

         /* iterate through the remaining pixel groups (4 pixels/group) */
         pixel_groups = s->width / 4 - 1;
         while (pixel_groups--) {

             cur_byte = buf[stream_ptr++];
             u_pred += u_table[(cur_byte & 0xF0) >> 4];
             u_plane[u_ptr++] = u_pred;
             y_pred += y_table[cur_byte & 0x0F];
             y_plane[y_ptr++] = y_pred;

             cur_byte = buf[stream_ptr++];
             v_pred += v_table[(cur_byte & 0xF0) >> 4];
             v_plane[v_ptr++] = v_pred;
             y_pred += y_table[cur_byte & 0x0F];
             y_plane[y_ptr++] = y_pred;

             cur_byte = buf[stream_ptr++];
             y_pred += y_table[cur_byte & 0x0F];
             y_plane[y_ptr++] = y_pred;
             y_pred += y_table[(cur_byte & 0xF0) >> 4];
             y_plane[y_ptr++] = y_pred;

         }
     }
     }

     *got_frame = 1;

     return buf_size;
 }

 #if CONFIG_AURA_DECODER
 AVCodec ff_aura_decoder = {
     .name           = "aura",
     .long_name      = NULL_IF_CONFIG_SMALL("Auravision AURA"),
     .type           = AVMEDIA_TYPE_VIDEO,
     .id             = AV_CODEC_ID_AURA,
     .priv_data_size = sizeof(CyuvDecodeContext),
     .init           = cyuv_decode_init,
     .decode         = cyuv_decode_frame,
     .capabilities   = AV_CODEC_CAP_DR1,
     .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
 };
 #endif

 #if CONFIG_CYUV_DECODER
 AVCodec ff_cyuv_decoder = {
     .name           = "cyuv",
     .long_name      = NULL_IF_CONFIG_SMALL("Creative YUV (CYUV)"),
     .type           = AVMEDIA_TYPE_VIDEO,
     .id             = AV_CODEC_ID_CYUV,
     .priv_data_size = sizeof(CyuvDecodeContext),
     .init           = cyuv_decode_init,
     .decode         = cyuv_decode_frame,
     .capabilities   = AV_CODEC_CAP_DR1,
     .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
 };
 #endif
	/*
	* Creative YUV (CYUV) Video Decoder
	* by Mike Melanson (melanson@pcisys.net)
	* based on "Creative YUV (CYUV) stream format for AVI":
	* http://www.csse.monash.edu.au/~timf/videocodec/cyuv.txt
	*
	* Copyright (C) 2003 The FFmpeg project
	*
	* 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
	* Creative YUV (CYUV) Video Decoder.
	*/

	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>

	#include "avcodec.h"
	#include "internal.h"
	#include "libavutil/internal.h"


	typedef struct CyuvDecodeContext {
	AVCodecContext *avctx;
	int width, height;
	} CyuvDecodeContext;

	static av_cold int cyuv_decode_init(AVCodecContext *avctx)
	{
	CyuvDecodeContext *s = avctx->priv_data;

	s->avctx = avctx;
	s->width = avctx->width;
	/* width needs to be divisible by 4 for this codec to work */
	if (s->width & 0x3)
	return AVERROR_INVALIDDATA;
	s->height = avctx->height;

	return 0;
	}

	static int cyuv_decode_frame(AVCodecContext *avctx,
	void data, int got_frame,
	AVPacket *avpkt)
	{
	const uint8_t *buf = avpkt->data;
	int buf_size = avpkt->size;
	CyuvDecodeContext *s=avctx->priv_data;
	AVFrame *frame = data;

	unsigned char *y_plane;
	unsigned char *u_plane;
	unsigned char *v_plane;
	int y_ptr;
	int u_ptr;
	int v_ptr;

	/* prediction error tables (make it clear that they are signed values) */
	const signed char y_table = (const signed char)buf + 0;
	const signed char u_table = (const signed char)buf + 16;
	const signed char v_table = (const signed char)buf + 32;

	unsigned char y_pred, u_pred, v_pred;
	int stream_ptr;
	unsigned char cur_byte;
	int pixel_groups;
	int rawsize = s->height * FFALIGN(s->width,2) * 2;
	int ret;

	if (avctx->codec_id == AV_CODEC_ID_AURA) {
	y_table = u_table;
	u_table = v_table;
	}
	/* sanity check the buffer size: A buffer has 3x16-bytes tables
	* followed by (height) lines each with 3 bytes to represent groups
	* of 4 pixels. Thus, the total size of the buffer ought to be:
	* (3 * 16) + height * (width * 3 / 4) */
	if (buf_size == 48 + s->height * (s->width * 3 / 4)) {
	avctx->pix_fmt = AV_PIX_FMT_YUV411P;
	} else if(buf_size == rawsize ) {
	avctx->pix_fmt = AV_PIX_FMT_UYVY422;
	} else {
	av_log(avctx, AV_LOG_ERROR, "got a buffer with %d bytes when %d were expected\n",
	buf_size, 48 + s->height * (s->width * 3 / 4));
	return AVERROR_INVALIDDATA;
	}

	/* pixel data starts 48 bytes in, after 3x16-byte tables */
	stream_ptr = 48;

	if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
	return ret;

	y_plane = frame->data[0];
	u_plane = frame->data[1];
	v_plane = frame->data[2];

	if (buf_size == rawsize) {
	int linesize = FFALIGN(s->width,2) * 2;
	y_plane += frame->linesize[0] * s->height;
	for (stream_ptr = 0; stream_ptr < rawsize; stream_ptr += linesize) {
	y_plane -= frame->linesize[0];
	memcpy(y_plane, buf+stream_ptr, linesize);
	}
	} else {

	/* iterate through each line in the height */
	for (y_ptr = 0, u_ptr = 0, v_ptr = 0;
	y_ptr < (s->height * frame->linesize[0]);
	y_ptr += frame->linesize[0] - s->width,
	u_ptr += frame->linesize[1] - s->width / 4,
	v_ptr += frame->linesize[2] - s->width / 4) {

	/* reset predictors */
	cur_byte = buf[stream_ptr++];
	u_plane[u_ptr++] = u_pred = cur_byte & 0xF0;
	y_plane[y_ptr++] = y_pred = (cur_byte & 0x0F) << 4;

	cur_byte = buf[stream_ptr++];
	v_plane[v_ptr++] = v_pred = cur_byte & 0xF0;
	y_pred += y_table[cur_byte & 0x0F];
	y_plane[y_ptr++] = y_pred;

	cur_byte = buf[stream_ptr++];
	y_pred += y_table[cur_byte & 0x0F];
	y_plane[y_ptr++] = y_pred;
	y_pred += y_table[(cur_byte & 0xF0) >> 4];
	y_plane[y_ptr++] = y_pred;

	/* iterate through the remaining pixel groups (4 pixels/group) */
	pixel_groups = s->width / 4 - 1;
	while (pixel_groups--) {

	cur_byte = buf[stream_ptr++];
	u_pred += u_table[(cur_byte & 0xF0) >> 4];
	u_plane[u_ptr++] = u_pred;
	y_pred += y_table[cur_byte & 0x0F];
	y_plane[y_ptr++] = y_pred;

	cur_byte = buf[stream_ptr++];
	v_pred += v_table[(cur_byte & 0xF0) >> 4];
	v_plane[v_ptr++] = v_pred;
	y_pred += y_table[cur_byte & 0x0F];
	y_plane[y_ptr++] = y_pred;

	cur_byte = buf[stream_ptr++];
	y_pred += y_table[cur_byte & 0x0F];
	y_plane[y_ptr++] = y_pred;
	y_pred += y_table[(cur_byte & 0xF0) >> 4];
	y_plane[y_ptr++] = y_pred;

	}
	}
	}

	*got_frame = 1;

	return buf_size;
	}

	#if CONFIG_AURA_DECODER
	AVCodec ff_aura_decoder = {
	.name = "aura",
	.long_name = NULL_IF_CONFIG_SMALL("Auravision AURA"),
	.type = AVMEDIA_TYPE_VIDEO,
	.id = AV_CODEC_ID_AURA,
	.priv_data_size = sizeof(CyuvDecodeContext),
	.init = cyuv_decode_init,
	.decode = cyuv_decode_frame,
	.capabilities = AV_CODEC_CAP_DR1,
	.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
	};
	#endif

	#if CONFIG_CYUV_DECODER
	AVCodec ff_cyuv_decoder = {
	.name = "cyuv",
	.long_name = NULL_IF_CONFIG_SMALL("Creative YUV (CYUV)"),
	.type = AVMEDIA_TYPE_VIDEO,
	.id = AV_CODEC_ID_CYUV,
	.priv_data_size = sizeof(CyuvDecodeContext),
	.init = cyuv_decode_init,
	.decode = cyuv_decode_frame,
	.capabilities = AV_CODEC_CAP_DR1,
	.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
	};
	#endif