ffmpeg/libavcodec/cljr.c

201 lines
6.0 KiB
C

/*
* Cirrus Logic AccuPak (CLJR) codec
* Copyright (c) 2003 Alex Beregszaszi
*
* 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
* Cirrus Logic AccuPak codec.
*/
#include "avcodec.h"
#include "libavutil/opt.h"
#include "get_bits.h"
#include "put_bits.h"
typedef struct CLJRContext {
AVClass *avclass;
AVFrame picture;
int dither_type;
} CLJRContext;
static av_cold int common_init(AVCodecContext *avctx)
{
CLJRContext * const a = avctx->priv_data;
avcodec_get_frame_defaults(&a->picture);
avctx->coded_frame = &a->picture;
return 0;
}
#if CONFIG_CLJR_DECODER
static int decode_frame(AVCodecContext *avctx,
void *data, int *data_size,
AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
CLJRContext * const a = avctx->priv_data;
GetBitContext gb;
AVFrame *picture = data;
AVFrame * const p = &a->picture;
int x, y;
if (p->data[0])
avctx->release_buffer(avctx, p);
if (buf_size / avctx->height < avctx->width) {
av_log(avctx, AV_LOG_ERROR,
"Resolution larger than buffer size. Invalid header?\n");
return AVERROR_INVALIDDATA;
}
p->reference = 0;
if (avctx->get_buffer(avctx, p) < 0) {
av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
return -1;
}
p->pict_type = AV_PICTURE_TYPE_I;
p->key_frame = 1;
init_get_bits(&gb, buf, buf_size * 8);
for (y = 0; y < avctx->height; y++) {
uint8_t *luma = &a->picture.data[0][y * a->picture.linesize[0]];
uint8_t *cb = &a->picture.data[1][y * a->picture.linesize[1]];
uint8_t *cr = &a->picture.data[2][y * a->picture.linesize[2]];
for (x = 0; x < avctx->width; x += 4) {
luma[3] = get_bits(&gb, 5) << 3;
luma[2] = get_bits(&gb, 5) << 3;
luma[1] = get_bits(&gb, 5) << 3;
luma[0] = get_bits(&gb, 5) << 3;
luma += 4;
*(cb++) = get_bits(&gb, 6) << 2;
*(cr++) = get_bits(&gb, 6) << 2;
}
}
*picture = a->picture;
*data_size = sizeof(AVPicture);
return buf_size;
}
static av_cold int decode_init(AVCodecContext *avctx)
{
avctx->pix_fmt = PIX_FMT_YUV411P;
return common_init(avctx);
}
static av_cold int decode_end(AVCodecContext *avctx)
{
CLJRContext *a = avctx->priv_data;
if (a->picture.data[0])
avctx->release_buffer(avctx, &a->picture);
return 0;
}
AVCodec ff_cljr_decoder = {
.name = "cljr",
.type = AVMEDIA_TYPE_VIDEO,
.id = CODEC_ID_CLJR,
.priv_data_size = sizeof(CLJRContext),
.init = decode_init,
.close = decode_end,
.decode = decode_frame,
.capabilities = CODEC_CAP_DR1,
.long_name = NULL_IF_CONFIG_SMALL("Cirrus Logic AccuPak"),
};
#endif
#if CONFIG_CLJR_ENCODER
static int encode_frame(AVCodecContext *avctx, unsigned char *buf,
int buf_size, void *data)
{
CLJRContext *a = avctx->priv_data;
PutBitContext pb;
AVFrame *p = data;
int x, y;
uint32_t dither= avctx->frame_number;
static const uint32_t ordered_dither[2][2] =
{
{ 0x10400000, 0x104F0000 },
{ 0xCB2A0000, 0xCB250000 },
};
p->pict_type = AV_PICTURE_TYPE_I;
p->key_frame = 1;
init_put_bits(&pb, buf, buf_size / 8);
for (y = 0; y < avctx->height; y++) {
uint8_t *luma = &p->data[0][y * p->linesize[0]];
uint8_t *cb = &p->data[1][y * p->linesize[1]];
uint8_t *cr = &p->data[2][y * p->linesize[2]];
for (x = 0; x < avctx->width; x += 4) {
switch (a->dither_type) {
case 0: dither = 0x492A0000; break;
case 1: dither = dither * 1664525 + 1013904223; break;
case 2: dither = ordered_dither[ y&1 ][ (x>>2)&1 ];break;
}
put_bits(&pb, 5, (luma[3] + (dither>>29) ) >> 3);
put_bits(&pb, 5, (luma[2] + ((dither>>26)&7)) >> 3);
put_bits(&pb, 5, (luma[1] + ((dither>>23)&7)) >> 3);
put_bits(&pb, 5, (luma[0] + ((dither>>20)&7)) >> 3);
luma += 4;
put_bits(&pb, 6, (*(cb++) + ((dither>>18)&3)) >> 2);
put_bits(&pb, 6, (*(cr++) + ((dither>>16)&3)) >> 2);
}
}
flush_put_bits(&pb);
return put_bits_count(&pb) / 8;
}
#define OFFSET(x) offsetof(CLJRContext, x)
#define VE AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
static const AVOption options[] = {
{ "dither_type", "Dither type", OFFSET(dither_type), AV_OPT_TYPE_INT, { .dbl=1 }, 0, 2, VE},
{ NULL },
};
static const AVClass class = {
.class_name = "cljr encoder",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
};
AVCodec ff_cljr_encoder = {
.name = "cljr",
.type = AVMEDIA_TYPE_VIDEO,
.id = CODEC_ID_CLJR,
.priv_data_size = sizeof(CLJRContext),
.init = common_init,
.encode = encode_frame,
.pix_fmts = (const enum PixelFormat[]) { PIX_FMT_YUV411P,
PIX_FMT_NONE },
.long_name = NULL_IF_CONFIG_SMALL("Cirrus Logic AccuPak"),
.priv_class = &class,
};
#endif