0,0 → 1,202 |
/* |
* 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 = CODEC_CAP_DR1, |
}; |
#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 = CODEC_CAP_DR1, |
}; |
#endif |