ffmpeg/libavcodec/xbmenc.c

99 lines
3.1 KiB
C

/*
* XBM image format
*
* Copyright (c) 2012 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 "avcodec.h"
#include "codec_internal.h"
#include "encode.h"
#define ANSI_MIN_READLINE 509
static int xbm_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
const AVFrame *p, int *got_packet)
{
int i, j, l, commas, ret, size, linesize, lineout, rowsout;
const uint8_t *ptr;
uint8_t *buf;
linesize = lineout = (avctx->width + 7) / 8;
commas = avctx->height * linesize;
/* ANSI worst case minimum readline is 509 chars. */
rowsout = avctx->height;
if (lineout > (ANSI_MIN_READLINE / 6)) {
lineout = ANSI_MIN_READLINE / 6;
rowsout = (commas + lineout - 1) / lineout;
}
size = rowsout * (lineout * 6 + 1) + 106;
if ((ret = ff_alloc_packet(avctx, pkt, size)) < 0)
return ret;
buf = pkt->data;
ptr = p->data[0];
buf += snprintf(buf, 32, "#define image_width %u\n", avctx->width);
buf += snprintf(buf, 33, "#define image_height %u\n", avctx->height);
buf += snprintf(buf, 39, "static unsigned char image_bits[] = {\n");
for (i = 0, l = lineout; i < avctx->height; i++) {
for (j = 0; j < linesize; j++) {
// 0..15 bitreversed as chars
static const char lut[] = {
'0', '8', '4', 'C', '2', 'A', '6', 'E',
'1', '9', '5', 'D', '3', 'B', '7', 'F'
};
buf[0] = ' ';
buf[1] = '0';
buf[2] = 'x';
buf[3] = lut[*ptr & 0xF];
buf[4] = lut[*ptr >> 4];
buf += 5;
ptr++;
if (--commas <= 0) {
*buf++ = '\n';
break;
}
*buf++ = ',';
if (--l <= 0) {
*buf++ = '\n';
l = lineout;
}
}
ptr += p->linesize[0] - linesize;
}
buf += snprintf(buf, 5, " };\n");
pkt->size = buf - pkt->data;
*got_packet = 1;
return 0;
}
const FFCodec ff_xbm_encoder = {
.p.name = "xbm",
CODEC_LONG_NAME("XBM (X BitMap) image"),
.p.type = AVMEDIA_TYPE_VIDEO,
.p.id = AV_CODEC_ID_XBM,
.p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE,
FF_CODEC_ENCODE_CB(xbm_encode_frame),
.p.pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_MONOWHITE,
AV_PIX_FMT_NONE },
};