ffmpeg/libavcodec/qoienc.c

140 lines
4.8 KiB
C

/*
* QOI image format encoder
*
* 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 "libavutil/imgutils.h"
#include "avcodec.h"
#include "bytestream.h"
#include "codec_internal.h"
#include "encode.h"
#include "qoi.h"
static int qoi_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
const AVFrame *pict, int *got_packet)
{
const int channels = 3 + (avctx->pix_fmt == AV_PIX_FMT_RGBA);
uint8_t px_prev[4] = { 0, 0, 0, 255 };
uint8_t px[4] = { 0, 0, 0, 255 };
uint8_t index[64][4] = { 0 };
int64_t packet_size;
uint8_t *buf, *src;
int ret, run = 0;
packet_size = avctx->width * avctx->height * (channels + 1LL) + 14LL + 8LL;
if ((ret = ff_alloc_packet(avctx, pkt, packet_size)) < 0)
return ret;
buf = pkt->data;
src = pict->data[0];
bytestream_put_buffer(&buf, "qoif", 4);
bytestream_put_be32(&buf, avctx->width);
bytestream_put_be32(&buf, avctx->height);
bytestream_put_byte(&buf, channels);
bytestream_put_byte(&buf, avctx->color_trc == AVCOL_TRC_LINEAR);
for (int y = 0; y < avctx->height; y++) {
for (int x = 0; x < avctx->width; x++) {
memcpy(px, src + x * channels, channels);
if (!memcmp(px, px_prev, 4)) {
run++;
if (run == 62) {
bytestream_put_byte(&buf, QOI_OP_RUN | (run - 1));
run = 0;
}
} else {
int index_pos;
if (run > 0) {
bytestream_put_byte(&buf, QOI_OP_RUN | (run - 1));
run = 0;
}
index_pos = QOI_COLOR_HASH(px) & 63;
if (!memcmp(index[index_pos], px, 4)) {
bytestream_put_byte(&buf, QOI_OP_INDEX | index_pos);
} else {
memcpy(index[index_pos], px, 4);
if (px[3] == px_prev[3]) {
int8_t vr = px[0] - px_prev[0];
int8_t vg = px[1] - px_prev[1];
int8_t vb = px[2] - px_prev[2];
int8_t vg_r = vr - vg;
int8_t vg_b = vb - vg;
if (vr > -3 && vr < 2 &&
vg > -3 && vg < 2 &&
vb > -3 && vb < 2) {
bytestream_put_byte(&buf, QOI_OP_DIFF | (vr + 2) << 4 | (vg + 2) << 2 | (vb + 2));
} else if (vg_r > -9 && vg_r < 8 &&
vg > -33 && vg < 32 &&
vg_b > -9 && vg_b < 8) {
bytestream_put_byte(&buf, QOI_OP_LUMA | (vg + 32));
bytestream_put_byte(&buf, (vg_r + 8) << 4 | (vg_b + 8));
} else {
bytestream_put_byte(&buf, QOI_OP_RGB);
bytestream_put_byte(&buf, px[0]);
bytestream_put_byte(&buf, px[1]);
bytestream_put_byte(&buf, px[2]);
}
} else {
bytestream_put_byte(&buf, QOI_OP_RGBA);
bytestream_put_byte(&buf, px[0]);
bytestream_put_byte(&buf, px[1]);
bytestream_put_byte(&buf, px[2]);
bytestream_put_byte(&buf, px[3]);
}
}
}
memcpy(px_prev, px, 4);
}
src += pict->linesize[0];
}
if (run)
bytestream_put_byte(&buf, QOI_OP_RUN | (run - 1));
bytestream_put_be64(&buf, 0x01);
pkt->size = buf - pkt->data;
*got_packet = 1;
return 0;
}
const FFCodec ff_qoi_encoder = {
.p.name = "qoi",
.p.long_name = NULL_IF_CONFIG_SMALL("QOI (Quite OK Image format) image"),
.p.type = AVMEDIA_TYPE_VIDEO,
.p.id = AV_CODEC_ID_QOI,
.p.capabilities = AV_CODEC_CAP_FRAME_THREADS,
FF_CODEC_ENCODE_CB(qoi_encode_frame),
.p.pix_fmts = (const enum AVPixelFormat[]){
AV_PIX_FMT_RGBA, AV_PIX_FMT_RGB24,
AV_PIX_FMT_NONE
},
};