FFmpeg/libavcodec/mscc.c
Andreas Rheinhardt 20f9727018 avcodec/codec_internal: Add FFCodec, hide internal part of AVCodec
Up until now, codec.h contains both public and private parts
of AVCodec. This exposes the internals of AVCodec to users
and leads them into the temptation of actually using them
and forces us to forward-declare structures and types that
users can't use at all.

This commit changes this by adding a new structure FFCodec to
codec_internal.h that extends AVCodec, i.e. contains the public
AVCodec as first member; the private fields of AVCodec are moved
to this structure, leaving codec.h clean.

Reviewed-by: Anton Khirnov <anton@khirnov.net>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2022-03-21 01:33:09 +01:00

274 lines
8.3 KiB
C

/*
* 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 "codec_internal.h"
#include "internal.h"
#include "zlib_wrapper.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;
FFZStream zstream;
uint32_t pal[256];
} MSCCContext;
static int rle_uncompress(AVCodecContext *avctx, GetByteContext *gb, PutByteContext *pb)
{
MSCCContext *s = avctx->priv_data;
unsigned x = 0, y = 0;
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;
}
}
x += run;
} else {
unsigned copy = bytestream2_get_byte(gb);
if (copy == 0) {
x = 0;
y++;
bytestream2_seek_p(pb, y * avctx->width * s->bpp, SEEK_SET);
} else if (copy == 1) {
return 0;
} else if (copy == 2) {
x += bytestream2_get_byte(gb);
y += bytestream2_get_byte(gb);
bytestream2_seek_p(pb, y * avctx->width * s->bpp + x * s->bpp, SEEK_SET);
} 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;
}
}
if (s->bpp == 1 && (copy & 1))
bytestream2_skip(gb, 1);
x += copy;
}
}
}
return AVERROR_INVALIDDATA;
}
static int decode_frame(AVCodecContext *avctx,
void *data, int *got_frame,
AVPacket *avpkt)
{
MSCCContext *s = avctx->priv_data;
z_stream *const zstream = &s->zstream.zstream;
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 buf_size;
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;
}
if (avctx->pix_fmt == AV_PIX_FMT_PAL8) {
size_t size;
const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, &size);
if (pal && size == AVPALETTE_SIZE) {
frame->palette_has_changed = 1;
for (j = 0; j < 256; j++)
s->pal[j] = 0xFF000000 | AV_RL32(pal + j * 4);
} else if (pal) {
av_log(avctx, AV_LOG_ERROR,
"Palette size %"SIZE_SPECIFIER" is wrong\n", size);
}
memcpy(frame->data[1], s->pal, AVPALETTE_SIZE);
}
ret = inflateReset(zstream);
if (ret != Z_OK) {
av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
return AVERROR_UNKNOWN;
}
zstream->next_in = buf;
zstream->avail_in = buf_size;
zstream->next_out = s->decomp_buf;
zstream->avail_out = s->decomp_size;
ret = inflate(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, zstream->total_out);
bytestream2_init_writer(&pb, s->uncomp_buf, s->uncomp_size);
ret = rle_uncompress(avctx, &gb, &pb);
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 stride;
switch (avctx->bits_per_coded_sample) {
case 8: avctx->pix_fmt = AV_PIX_FMT_PAL8; 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;
stride = 4 * ((avctx->width * avctx->bits_per_coded_sample + 31) / 32);
s->decomp_size = 2 * avctx->height * stride;
if (!(s->decomp_buf = av_malloc(s->decomp_size)))
return AVERROR(ENOMEM);
s->uncomp_size = avctx->height * stride;
if (!(s->uncomp_buf = av_malloc(s->uncomp_size)))
return AVERROR(ENOMEM);
return ff_inflate_init(&s->zstream, avctx);
}
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;
ff_inflate_end(&s->zstream);
return 0;
}
const FFCodec ff_mscc_decoder = {
.p.name = "mscc",
.p.long_name = NULL_IF_CONFIG_SMALL("Mandsoft Screen Capture Codec"),
.p.type = AVMEDIA_TYPE_VIDEO,
.p.id = AV_CODEC_ID_MSCC,
.priv_data_size = sizeof(MSCCContext),
.init = decode_init,
.close = decode_close,
.decode = decode_frame,
.p.capabilities = AV_CODEC_CAP_DR1,
.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP,
};
const FFCodec ff_srgc_decoder = {
.p.name = "srgc",
.p.long_name = NULL_IF_CONFIG_SMALL("Screen Recorder Gold Codec"),
.p.type = AVMEDIA_TYPE_VIDEO,
.p.id = AV_CODEC_ID_SRGC,
.priv_data_size = sizeof(MSCCContext),
.init = decode_init,
.close = decode_close,
.decode = decode_frame,
.p.capabilities = AV_CODEC_CAP_DR1,
.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP,
};