mirror of https://git.ffmpeg.org/ffmpeg.git
289 lines
8.1 KiB
C
289 lines
8.1 KiB
C
/*
|
|
* vMix decoder
|
|
* Copyright (c) 2023 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 "libavutil/avassert.h"
|
|
#include "libavutil/intreadwrite.h"
|
|
#include "libavutil/mem_internal.h"
|
|
|
|
#include "avcodec.h"
|
|
#include "codec_internal.h"
|
|
#include "decode.h"
|
|
#define CACHED_BITSTREAM_READER !ARCH_X86_32
|
|
#include "golomb.h"
|
|
#include "get_bits.h"
|
|
#include "idctdsp.h"
|
|
#include "thread.h"
|
|
|
|
typedef struct SliceContext {
|
|
const uint8_t *dc_ptr;
|
|
const uint8_t *ac_ptr;
|
|
unsigned dc_size;
|
|
unsigned ac_size;
|
|
} SliceContext;
|
|
|
|
typedef struct VMIXContext {
|
|
int nb_slices;
|
|
|
|
int16_t factors[64];
|
|
uint8_t scan[64];
|
|
|
|
SliceContext slices[255];
|
|
|
|
IDCTDSPContext idsp;
|
|
} VMIXContext;
|
|
|
|
static const uint8_t quality[25] = {
|
|
1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 14, 16,
|
|
18, 20, 22, 24, 28, 32, 36, 40, 44, 48, 52, 56, 64,
|
|
};
|
|
|
|
static const uint8_t quant[64] = {
|
|
16, 16, 19, 22, 22, 26, 26, 27,
|
|
16, 16, 22, 22, 26, 27, 27, 29,
|
|
19, 22, 26, 26, 27, 29, 29, 35,
|
|
22, 24, 27, 27, 29, 32, 34, 38,
|
|
26, 27, 29, 29, 32, 35, 38, 46,
|
|
27, 29, 34, 34, 35, 40, 46, 56,
|
|
29, 34, 34, 37, 40, 48, 56, 69,
|
|
34, 37, 38, 40, 48, 58, 69, 83,
|
|
};
|
|
|
|
static av_cold int decode_init(AVCodecContext *avctx)
|
|
{
|
|
VMIXContext *s = avctx->priv_data;
|
|
|
|
avctx->bits_per_raw_sample = 8;
|
|
avctx->pix_fmt = AV_PIX_FMT_YUV422P;
|
|
|
|
avctx->coded_width = FFALIGN(avctx->width, 16);
|
|
avctx->coded_height = FFALIGN(avctx->height, 16);
|
|
|
|
ff_idctdsp_init(&s->idsp, avctx);
|
|
ff_permute_scantable(s->scan, ff_zigzag_direct,
|
|
s->idsp.idct_permutation);
|
|
return 0;
|
|
}
|
|
|
|
static inline int get_se_golomb_vmix(GetBitContext *gb)
|
|
{
|
|
unsigned int buf = get_ue_golomb_long(gb);
|
|
int sign = (buf & 1) - 1;
|
|
return ((buf >> 1) ^ (~sign));
|
|
}
|
|
|
|
static int decode_dcac(AVCodecContext *avctx,
|
|
GetBitContext *dc_gb, GetBitContext *ac_gb,
|
|
unsigned *dcrun, unsigned *acrun,
|
|
AVFrame *frame, int width, int by, int plane)
|
|
{
|
|
const ptrdiff_t linesize = frame->linesize[plane];
|
|
uint8_t *dst = frame->data[plane] + by * linesize;
|
|
unsigned dc_run = *dcrun, ac_run = *acrun;
|
|
LOCAL_ALIGNED_32(int16_t, block, [64]);
|
|
VMIXContext *s = avctx->priv_data;
|
|
const int16_t *factors = s->factors;
|
|
const uint8_t *scan = s->scan;
|
|
const int add = plane ? 0 : 1024;
|
|
int i, dc_v = 0, ac_v = 0, dc = 0;
|
|
|
|
for (int y = 0; y < 2; y++) {
|
|
for (int x = 0; x < width; x += 8) {
|
|
memset(block, 0, sizeof(*block)*64);
|
|
|
|
if (dc_run > 0) {
|
|
dc_run--;
|
|
} else {
|
|
dc_v = get_se_golomb_vmix(dc_gb);
|
|
dc += dc_v;
|
|
if (!dc_v)
|
|
dc_run = get_ue_golomb_long(dc_gb);
|
|
}
|
|
|
|
for (int n = 0; n < 64; n++) {
|
|
if (ac_run > 0) {
|
|
ac_run--;
|
|
continue;
|
|
}
|
|
|
|
ac_v = get_se_golomb_vmix(ac_gb);
|
|
i = scan[n];
|
|
block[i] = (ac_v * factors[i]) >> 4;
|
|
if (!ac_v)
|
|
ac_run = get_ue_golomb_long(ac_gb);
|
|
}
|
|
|
|
block[0] = ((dc + add) * 16) >> 4;
|
|
s->idsp.idct_put(dst + x, linesize, block);
|
|
}
|
|
|
|
dst += 8 * linesize;
|
|
}
|
|
|
|
*dcrun = dc_run;
|
|
*acrun = ac_run;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int decode_slice(AVCodecContext *avctx, AVFrame *frame,
|
|
const uint8_t *dc_src, unsigned dc_slice_size,
|
|
const uint8_t *ac_src, unsigned ac_slice_size,
|
|
int by)
|
|
{
|
|
unsigned dc_run = 0, ac_run = 0;
|
|
GetBitContext dc_gb, ac_gb;
|
|
int ret;
|
|
|
|
ret = init_get_bits8(&dc_gb, dc_src, dc_slice_size);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
ret = init_get_bits8(&ac_gb, ac_src, ac_slice_size);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
for (int p = 0; p < 3; p++) {
|
|
const int rshift = !!p;
|
|
ret = decode_dcac(avctx, &dc_gb, &ac_gb,
|
|
&dc_run, &ac_run, frame,
|
|
frame->width >> rshift, by, p);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
if (get_bits_left(&dc_gb) < 0)
|
|
return AVERROR_INVALIDDATA;
|
|
if (get_bits_left(&ac_gb) < 0)
|
|
return AVERROR_INVALIDDATA;
|
|
|
|
align_get_bits(&dc_gb);
|
|
align_get_bits(&ac_gb);
|
|
}
|
|
|
|
if (get_bits_left(&dc_gb) > 0)
|
|
return AVERROR_INVALIDDATA;
|
|
if (get_bits_left(&ac_gb) > 0)
|
|
return AVERROR_INVALIDDATA;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int decode_slices(AVCodecContext *avctx, void *arg,
|
|
int n, int thread_nb)
|
|
{
|
|
VMIXContext *s = avctx->priv_data;
|
|
const uint8_t *dc_slice_ptr = s->slices[n].dc_ptr;
|
|
const uint8_t *ac_slice_ptr = s->slices[n].ac_ptr;
|
|
unsigned dc_slice_size = s->slices[n].dc_size;
|
|
unsigned ac_slice_size = s->slices[n].ac_size;
|
|
AVFrame *frame = arg;
|
|
|
|
return decode_slice(avctx, frame, dc_slice_ptr, dc_slice_size,
|
|
ac_slice_ptr, ac_slice_size, n * 16);
|
|
}
|
|
|
|
static int decode_frame(AVCodecContext *avctx,
|
|
AVFrame *frame, int *got_frame,
|
|
AVPacket *avpkt)
|
|
{
|
|
VMIXContext *s = avctx->priv_data;
|
|
unsigned offset = 3, q;
|
|
int ret;
|
|
|
|
if (avpkt->size <= 7)
|
|
return AVERROR_INVALIDDATA;
|
|
|
|
if (avpkt->data[0] != 0x01)
|
|
return AVERROR_INVALIDDATA;
|
|
|
|
q = av_clip(99 - av_clip(avpkt->data[1], 0, 99), 0, FF_ARRAY_ELEMS(quality) - 1);
|
|
for (int n = 0; n < 64; n++)
|
|
s->factors[n] = quant[n] * quality[q];
|
|
|
|
s->nb_slices = avpkt->data[2];
|
|
if (!s->nb_slices || s->nb_slices > (avctx->height + 15) / 16)
|
|
return AVERROR_INVALIDDATA;
|
|
|
|
for (int n = 0; n < s->nb_slices; n++) {
|
|
unsigned slice_size;
|
|
|
|
if (offset + 4 > avpkt->size)
|
|
return AVERROR_INVALIDDATA;
|
|
|
|
slice_size = AV_RL32(avpkt->data + offset);
|
|
if (slice_size > avpkt->size)
|
|
return AVERROR_INVALIDDATA;
|
|
|
|
if (avpkt->size - slice_size - 4LL < offset)
|
|
return AVERROR_INVALIDDATA;
|
|
|
|
s->slices[n].dc_size = slice_size;
|
|
s->slices[n].dc_ptr = avpkt->data + offset + 4;
|
|
offset += slice_size + 4;
|
|
}
|
|
|
|
for (int n = 0; n < s->nb_slices; n++) {
|
|
unsigned slice_size;
|
|
|
|
if (offset + 4 > avpkt->size)
|
|
return AVERROR_INVALIDDATA;
|
|
|
|
slice_size = AV_RL32(avpkt->data + offset);
|
|
if (slice_size > avpkt->size)
|
|
return AVERROR_INVALIDDATA;
|
|
|
|
if (avpkt->size - slice_size - 4LL < offset)
|
|
return AVERROR_INVALIDDATA;
|
|
|
|
s->slices[n].ac_size = slice_size;
|
|
s->slices[n].ac_ptr = avpkt->data + offset + 4;
|
|
offset += slice_size + 4;
|
|
}
|
|
|
|
ret = ff_thread_get_buffer(avctx, frame, 0);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
avctx->execute2(avctx, decode_slices, frame, NULL, s->nb_slices);
|
|
|
|
frame->pict_type = AV_PICTURE_TYPE_I;
|
|
frame->flags |= AV_FRAME_FLAG_KEY;
|
|
|
|
*got_frame = 1;
|
|
|
|
return avpkt->size;
|
|
}
|
|
|
|
const FFCodec ff_vmix_decoder = {
|
|
.p.name = "vmix",
|
|
CODEC_LONG_NAME("vMix Video"),
|
|
.p.type = AVMEDIA_TYPE_VIDEO,
|
|
.p.id = AV_CODEC_ID_VMIX,
|
|
.priv_data_size = sizeof(VMIXContext),
|
|
.init = decode_init,
|
|
FF_CODEC_DECODE_CB(decode_frame),
|
|
.p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS |
|
|
AV_CODEC_CAP_SLICE_THREADS,
|
|
};
|