libavcodec/truemotion2rt.c - third_party/ffmpeg - Git at Google

 /*
  * Duck TrueMotion 2.0 Real Time Decoder
  *
  * 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
  */

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

 #include "avcodec.h"
 #define BITSTREAM_READER_LE
 #include "get_bits.h"
 #include "internal.h"
 #include "libavutil/imgutils.h"
 #include "libavutil/internal.h"
 #include "libavutil/intreadwrite.h"
 #include "libavutil/mem.h"

 typedef struct TrueMotion2RTContext {
     GetBitContext gb;
     const uint8_t *buf;
     int size;
     int delta_size;
     int hscale;
 } TrueMotion2RTContext;

 static av_cold int decode_init(AVCodecContext *avctx)
 {
     avctx->pix_fmt = AV_PIX_FMT_YUV410P;
     return 0;
 }

 /* Returns the number of bytes consumed from the bytestream. Returns -1 if
  * there was an error while decoding the header */
 static int truemotion2rt_decode_header(AVCodecContext *avctx)
 {
     TrueMotion2RTContext *s = avctx->priv_data;
     uint8_t header_buffer[128] = { 0 };  /* logical maximum size of the header */
     int i, header_size;

     header_size = ((s->buf[0] >> 5) | (s->buf[0] << 3)) & 0x7f;
     if (header_size < 10) {
         av_log(avctx, AV_LOG_ERROR, "invalid header size (%d)\n", header_size);
         return AVERROR_INVALIDDATA;
     }

     if (header_size + 1 > s->size) {
         av_log(avctx, AV_LOG_ERROR, "Input packet too small.\n");
         return AVERROR_INVALIDDATA;
     }

     /* unscramble the header bytes with a XOR operation */
     for (i = 1; i < header_size; i++)
         header_buffer[i - 1] = s->buf[i] ^ s->buf[i + 1];

     s->delta_size = header_buffer[1];
     s->hscale = 1 + !!header_buffer[3];
     if (s->delta_size < 2 || s->delta_size > 4)
         return AVERROR_INVALIDDATA;

     avctx->height = AV_RL16(header_buffer + 5);
     avctx->width  = AV_RL16(header_buffer + 7);

     return header_size;
 }

 static const int16_t delta_tab4[] = {
     1, -1, 2, -3, 8, -8, 18, -18, 36, -36, 54, -54, 96, -96, 144, -144
 };

 static const int16_t delta_tab3[] = {
     2, -3, 8, -8, 18, -18, 36, -36
 };

 static const int16_t delta_tab2[] = {
     5, -7, 36, -36
 };

 static const int16_t *const delta_tabs[] = {
     delta_tab2, delta_tab3, delta_tab4,
 };

 static int decode_frame(AVCodecContext *avctx,
                         void *data, int *got_frame,
                         AVPacket *avpkt)
 {
     TrueMotion2RTContext *s = avctx->priv_data;
     const uint8_t *buf = avpkt->data;
     int ret, buf_size = avpkt->size;
     AVFrame * const p = data;
     GetBitContext *gb = &s->gb;
     uint8_t *dst;
     int x, y, delta_mode;

     s->buf = buf;
     s->size = buf_size;

     if ((ret = truemotion2rt_decode_header(avctx)) < 0)
         return ret;

     if ((ret = init_get_bits8(gb, buf + ret, buf_size - ret)) < 0)
         return ret;

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

     skip_bits(gb, 32);
     delta_mode = s->delta_size - 2;
     dst = p->data[0];
     for (y = 0; y < avctx->height; y++) {
         int diff = 0;
         for (x = 0; x < avctx->width; x += s->hscale) {
             diff  += delta_tabs[delta_mode][get_bits(gb, s->delta_size)];
             dst[x] = av_clip_uint8((y ? dst[x - p->linesize[0]] : 0) + diff);
         }
         dst += p->linesize[0];
     }

     if (s->hscale > 1) {
         dst = p->data[0];
         for (y = 0; y < avctx->height; y++) {
             for (x = 1; x < avctx->width; x += s->hscale) {
                 dst[x] = dst[x - 1];
             }
             dst += p->linesize[0];
         }
     }

     dst = p->data[0];
     for (y = 0; y < avctx->height; y++) {
         for (x = 0; x < avctx->width; x++)
             dst[x] = av_clip_uint8(dst[x] + (dst[x] - 128) / 3);
         dst += p->linesize[0];
     }

     dst = p->data[1];
     for (y = 0; y < avctx->height >> 2; y++) {
         int diff = 0;
         for (x = 0; x < avctx->width >> 2; x += s->hscale) {
             diff  += delta_tabs[delta_mode][get_bits(gb, s->delta_size)];
             dst[x] = av_clip_uint8((y ? dst[x - p->linesize[1]] : 128) + diff);
         }
         dst += p->linesize[1];
     }

     if (s->hscale > 1) {
         dst = p->data[1];
         for (y = 0; y < avctx->height >> 2; y++) {
             for (x = 1; x < avctx->width >> 2; x += s->hscale) {
                 dst[x] = dst[x - 1];
             }
             dst += p->linesize[1];
         }
     }

     dst = p->data[1];
     for (y = 0; y < avctx->height >> 2; y++) {
         for (x = 0; x < avctx->width >> 2; x++)
             dst[x] += (dst[x] - 128) / 8;
         dst += p->linesize[1];
     }

     dst = p->data[2];
     for (y = 0; y < avctx->height >> 2; y++) {
         int diff = 0;
         for (x = 0; x < avctx->width >> 2; x += s->hscale) {
             diff  += delta_tabs[delta_mode][get_bits(gb, s->delta_size)];
             dst[x] = av_clip_uint8((y ? dst[x - p->linesize[2]] : 128) + diff);
         }
         dst += p->linesize[2];
     }

     if (s->hscale > 1) {
         dst = p->data[2];
         for (y = 0; y < avctx->height >> 2; y++) {
             for (x = 1; x < avctx->width >> 2; x += s->hscale) {
                 dst[x] = dst[x - 1];
             }
             dst += p->linesize[2];
         }
     }

     dst = p->data[2];
     for (y = 0; y < avctx->height >> 2; y++) {
         for (x = 0; x < avctx->width >> 2; x++)
             dst[x] += (dst[x] - 128) / 8;
         dst += p->linesize[2];
     }

     p->pict_type = AV_PICTURE_TYPE_I;
     p->key_frame = 1;
     *got_frame   = 1;

     return buf_size;
 }

 AVCodec ff_truemotion2rt_decoder = {
     .name           = "truemotion2rt",
     .long_name      = NULL_IF_CONFIG_SMALL("Duck TrueMotion 2.0 Real Time"),
     .type           = AVMEDIA_TYPE_VIDEO,
     .id             = AV_CODEC_ID_TRUEMOTION2RT,
     .priv_data_size = sizeof(TrueMotion2RTContext),
     .init           = decode_init,
     .decode         = decode_frame,
     .capabilities   = AV_CODEC_CAP_DR1,
 };
	/*
	* Duck TrueMotion 2.0 Real Time Decoder
	*
	* 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
	*/

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

	#include "avcodec.h"
	#define BITSTREAM_READER_LE
	#include "get_bits.h"
	#include "internal.h"
	#include "libavutil/imgutils.h"
	#include "libavutil/internal.h"
	#include "libavutil/intreadwrite.h"
	#include "libavutil/mem.h"

	typedef struct TrueMotion2RTContext {
	GetBitContext gb;
	const uint8_t *buf;
	int size;
	int delta_size;
	int hscale;
	} TrueMotion2RTContext;

	static av_cold int decode_init(AVCodecContext *avctx)
	{
	avctx->pix_fmt = AV_PIX_FMT_YUV410P;
	return 0;
	}

	/* Returns the number of bytes consumed from the bytestream. Returns -1 if
	* there was an error while decoding the header */
	static int truemotion2rt_decode_header(AVCodecContext *avctx)
	{
	TrueMotion2RTContext *s = avctx->priv_data;
	uint8_t header_buffer[128] = { 0 }; /* logical maximum size of the header */
	int i, header_size;

	header_size = ((s->buf[0] >> 5) \| (s->buf[0] << 3)) & 0x7f;
	if (header_size < 10) {
	av_log(avctx, AV_LOG_ERROR, "invalid header size (%d)\n", header_size);
	return AVERROR_INVALIDDATA;
	}

	if (header_size + 1 > s->size) {
	av_log(avctx, AV_LOG_ERROR, "Input packet too small.\n");
	return AVERROR_INVALIDDATA;
	}

	/* unscramble the header bytes with a XOR operation */
	for (i = 1; i < header_size; i++)
	header_buffer[i - 1] = s->buf[i] ^ s->buf[i + 1];

	s->delta_size = header_buffer[1];
	s->hscale = 1 + !!header_buffer[3];
	if (s->delta_size < 2 \|\| s->delta_size > 4)
	return AVERROR_INVALIDDATA;

	avctx->height = AV_RL16(header_buffer + 5);
	avctx->width = AV_RL16(header_buffer + 7);

	return header_size;
	}

	static const int16_t delta_tab4[] = {
	1, -1, 2, -3, 8, -8, 18, -18, 36, -36, 54, -54, 96, -96, 144, -144
	};

	static const int16_t delta_tab3[] = {
	2, -3, 8, -8, 18, -18, 36, -36
	};

	static const int16_t delta_tab2[] = {
	5, -7, 36, -36
	};

	static const int16_t *const delta_tabs[] = {
	delta_tab2, delta_tab3, delta_tab4,
	};

	static int decode_frame(AVCodecContext *avctx,
	void data, int got_frame,
	AVPacket *avpkt)
	{
	TrueMotion2RTContext *s = avctx->priv_data;
	const uint8_t *buf = avpkt->data;
	int ret, buf_size = avpkt->size;
	AVFrame * const p = data;
	GetBitContext *gb = &s->gb;
	uint8_t *dst;
	int x, y, delta_mode;

	s->buf = buf;
	s->size = buf_size;

	if ((ret = truemotion2rt_decode_header(avctx)) < 0)
	return ret;

	if ((ret = init_get_bits8(gb, buf + ret, buf_size - ret)) < 0)
	return ret;

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

	skip_bits(gb, 32);
	delta_mode = s->delta_size - 2;
	dst = p->data[0];
	for (y = 0; y < avctx->height; y++) {
	int diff = 0;
	for (x = 0; x < avctx->width; x += s->hscale) {
	diff += delta_tabs[delta_mode][get_bits(gb, s->delta_size)];
	dst[x] = av_clip_uint8((y ? dst[x - p->linesize[0]] : 0) + diff);
	}
	dst += p->linesize[0];
	}

	if (s->hscale > 1) {
	dst = p->data[0];
	for (y = 0; y < avctx->height; y++) {
	for (x = 1; x < avctx->width; x += s->hscale) {
	dst[x] = dst[x - 1];
	}
	dst += p->linesize[0];
	}
	}

	dst = p->data[0];
	for (y = 0; y < avctx->height; y++) {
	for (x = 0; x < avctx->width; x++)
	dst[x] = av_clip_uint8(dst[x] + (dst[x] - 128) / 3);
	dst += p->linesize[0];
	}

	dst = p->data[1];
	for (y = 0; y < avctx->height >> 2; y++) {
	int diff = 0;
	for (x = 0; x < avctx->width >> 2; x += s->hscale) {
	diff += delta_tabs[delta_mode][get_bits(gb, s->delta_size)];
	dst[x] = av_clip_uint8((y ? dst[x - p->linesize[1]] : 128) + diff);
	}
	dst += p->linesize[1];
	}

	if (s->hscale > 1) {
	dst = p->data[1];
	for (y = 0; y < avctx->height >> 2; y++) {
	for (x = 1; x < avctx->width >> 2; x += s->hscale) {
	dst[x] = dst[x - 1];
	}
	dst += p->linesize[1];
	}
	}

	dst = p->data[1];
	for (y = 0; y < avctx->height >> 2; y++) {
	for (x = 0; x < avctx->width >> 2; x++)
	dst[x] += (dst[x] - 128) / 8;
	dst += p->linesize[1];
	}

	dst = p->data[2];
	for (y = 0; y < avctx->height >> 2; y++) {
	int diff = 0;
	for (x = 0; x < avctx->width >> 2; x += s->hscale) {
	diff += delta_tabs[delta_mode][get_bits(gb, s->delta_size)];
	dst[x] = av_clip_uint8((y ? dst[x - p->linesize[2]] : 128) + diff);
	}
	dst += p->linesize[2];
	}

	if (s->hscale > 1) {
	dst = p->data[2];
	for (y = 0; y < avctx->height >> 2; y++) {
	for (x = 1; x < avctx->width >> 2; x += s->hscale) {
	dst[x] = dst[x - 1];
	}
	dst += p->linesize[2];
	}
	}

	dst = p->data[2];
	for (y = 0; y < avctx->height >> 2; y++) {
	for (x = 0; x < avctx->width >> 2; x++)
	dst[x] += (dst[x] - 128) / 8;
	dst += p->linesize[2];
	}

	p->pict_type = AV_PICTURE_TYPE_I;
	p->key_frame = 1;
	*got_frame = 1;

	return buf_size;
	}

	AVCodec ff_truemotion2rt_decoder = {
	.name = "truemotion2rt",
	.long_name = NULL_IF_CONFIG_SMALL("Duck TrueMotion 2.0 Real Time"),
	.type = AVMEDIA_TYPE_VIDEO,
	.id = AV_CODEC_ID_TRUEMOTION2RT,
	.priv_data_size = sizeof(TrueMotion2RTContext),
	.init = decode_init,
	.decode = decode_frame,
	.capabilities = AV_CODEC_CAP_DR1,
	};