/*
* Mandsoft Screen Capture Codec decoder
*
* Copyright (c) 2017 Paul B Mahol
*
* 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"
#include "bytestream.h"
#include "internal.h"
#include <zlib.h>
typedef struct MSCCContext {
unsigned bpp;
unsigned int decomp_size;
uint8_t *decomp_buf;
unsigned int uncomp_size;
uint8_t *uncomp_buf;
z_stream zstream;
} MSCCContext;
static int rle_uncompress(AVCodecContext *avctx, GetByteContext *gb, PutByteContext *pb, int bpp)
{
while (bytestream2_get_bytes_left(gb) > 0) {
uint32_t fill;
int j;
unsigned run = bytestream2_get_byte(gb);
if (run) {
switch (avctx->bits_per_coded_sample) {
case 8:
fill = bytestream2_get_byte(gb);
break;
case 16:
fill = bytestream2_get_le16(gb);
break;
case 24:
fill = bytestream2_get_le24(gb);
break;
case 32:
fill = bytestream2_get_le32(gb);
break;
}
for (j = 0; j < run; j++) {
switch (avctx->bits_per_coded_sample) {
case 8:
bytestream2_put_byte(pb, fill);
break;
case 16:
bytestream2_put_le16(pb, fill);
break;
case 24:
bytestream2_put_le24(pb, fill);
break;
case 32:
bytestream2_put_le32(pb, fill);
break;
}
}
} else {
unsigned copy = bytestream2_get_byte(gb);
if (copy == 1) {
return 0;
} else if (copy == 2) {
unsigned x, y;
x = bytestream2_get_byte(gb);
y = bytestream2_get_byte(gb);
bytestream2_skip_p(pb, x * bpp);
bytestream2_skip_p(pb, y * bpp * avctx->width);
} else {
for (j = 0; j < copy; j++) {
switch (avctx->bits_per_coded_sample) {
case 8:
bytestream2_put_byte(pb, bytestream2_get_byte(gb));
break;
case 16:
bytestream2_put_le16(pb, bytestream2_get_le16(gb));
break;
case 24:
bytestream2_put_le24(pb, bytestream2_get_le24(gb));
break;
case 32:
bytestream2_put_le32(pb, bytestream2_get_le32(gb));
break;
}
}
}
}
}
return AVERROR_INVALIDDATA;
}
static int decode_frame(AVCodecContext *avctx,
void *data, int *got_frame,
AVPacket *avpkt)
{
MSCCContext *s = avctx->priv_data;
AVFrame *frame = data;
uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
GetByteContext gb;
PutByteContext pb;
int ret, j;
if (avpkt->size < 3)
return AVERROR_INVALIDDATA;
if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
return ret;
if (avctx->codec_id == AV_CODEC_ID_MSCC) {
avpkt->data[2] ^= avpkt->data[0];
buf += 2;
buf_size -= 2;
}
ret = inflateReset(&s->zstream);
if (ret != Z_OK) {
av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
return AVERROR_UNKNOWN;
}
s->zstream.next_in = buf;
s->zstream.avail_in = buf_size;
s->zstream.next_out = s->decomp_buf;
s->zstream.avail_out = s->decomp_size;
ret = inflate(&s->zstream, Z_FINISH);
if (ret != Z_STREAM_END) {
av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", ret);
return AVERROR_UNKNOWN;
}
bytestream2_init(&gb, s->decomp_buf, s->zstream.total_out);
bytestream2_init_writer(&pb, s->uncomp_buf, s->uncomp_size);
ret = rle_uncompress(avctx, &gb, &pb, s->bpp);
if (ret)
return ret;
for (j = 0; j < avctx->height; j++) {
memcpy(frame->data[0] + (avctx->height - j - 1) * frame->linesize[0],
s->uncomp_buf + s->bpp * j * avctx->width, s->bpp * avctx->width);
}
frame->key_frame = 1;
frame->pict_type = AV_PICTURE_TYPE_I;
*got_frame = 1;
return avpkt->size;
}
static av_cold int decode_init(AVCodecContext *avctx)
{
MSCCContext *s = avctx->priv_data;
int zret;
switch (avctx->bits_per_coded_sample) {
case 8: avctx->pix_fmt = AV_PIX_FMT_GRAY8; break;
case 16: avctx->pix_fmt = AV_PIX_FMT_RGB555; break;
case 24: avctx->pix_fmt = AV_PIX_FMT_BGR24; break;
case 32: avctx->pix_fmt = AV_PIX_FMT_BGRA; break;
default:
av_log(avctx, AV_LOG_ERROR, "Unsupported bitdepth %i\n", avctx->bits_per_coded_sample);
return AVERROR_INVALIDDATA;
}
s->bpp = avctx->bits_per_coded_sample >> 3;
memset(&s->zstream, 0, sizeof(z_stream));
s->decomp_size = 4 * avctx->height * ((avctx->width * avctx->bits_per_coded_sample + 31) / 32);
if (!(s->decomp_buf = av_malloc(s->decomp_size)))
return AVERROR(ENOMEM);
s->uncomp_size = 4 * avctx->height * ((avctx->width * avctx->bits_per_coded_sample + 31) / 32);
if (!(s->uncomp_buf = av_malloc(s->uncomp_size)))
return AVERROR(ENOMEM);
s->zstream.zalloc = Z_NULL;
s->zstream.zfree = Z_NULL;
s->zstream.opaque = Z_NULL;
zret = inflateInit(&s->zstream);
if (zret != Z_OK) {
av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
return AVERROR_UNKNOWN;
}
return 0;
}
static av_cold int decode_close(AVCodecContext *avctx)
{
MSCCContext *s = avctx->priv_data;
av_freep(&s->decomp_buf);
s->decomp_size = 0;
av_freep(&s->uncomp_buf);
s->uncomp_size = 0;
inflateEnd(&s->zstream);
return 0;
}
AVCodec ff_mscc_decoder = {
.name = "mscc",
.long_name = NULL_IF_CONFIG_SMALL("Mandsoft Screen Capture Codec"),
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_MSCC,
.priv_data_size = sizeof(MSCCContext),
.init = decode_init,
.close = decode_close,
.decode = decode_frame,
.capabilities = AV_CODEC_CAP_DR1,
};
AVCodec ff_srgc_decoder = {
.name = "srgc",
.long_name = NULL_IF_CONFIG_SMALL("Screen Recorder Gold Codec"),
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_SRGC,
.priv_data_size = sizeof(MSCCContext),
.init = decode_init,
.close = decode_close,
.decode = decode_frame,
.capabilities = AV_CODEC_CAP_DR1,
};