[FFmpeg-devel] [PATCH] XBM decoder
Paul B Mahol
onemda at gmail.com
Fri Mar 23 23:54:09 CET 2012
Signed-off-by: Paul B Mahol <onemda at gmail.com>
---
Changelog | 2 +-
doc/general.texi | 2 +-
libavcodec/Makefile | 1 +
libavcodec/allcodecs.c | 2 +-
libavcodec/xbmdec.c | 130 ++++++++++++++++++++++++++++++++++++++++++++++++
5 files changed, 134 insertions(+), 3 deletions(-)
create mode 100644 libavcodec/xbmdec.c
diff --git a/Changelog b/Changelog
index 6c9f551..aa6a811 100644
--- a/Changelog
+++ b/Changelog
@@ -15,7 +15,7 @@ version next:
- libutvideo encoder wrapper (--enable-libutvideo)
- swapuv filter
- bbox filter
-- XBM encoder
+- XBM encoder and decoder
- RealAudio Lossless decoder
- ZeroCodec decoder
- tile video filter
diff --git a/doc/general.texi b/doc/general.texi
index 1acdc24..555650a 100644
--- a/doc/general.texi
+++ b/doc/general.texi
@@ -402,7 +402,7 @@ following image formats are supported:
@tab YUV, JPEG and some extension is not supported yet.
@item Truevision Targa @tab X @tab X
@tab Targa (.TGA) image format
- at item XBM @tab X @tab
+ at item XBM @tab X @tab X
@tab X BitMap image format
@item XWD @tab X @tab X
@tab X Window Dump image format
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index ec29ce5..28988ec 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -486,6 +486,7 @@ OBJS-$(CONFIG_XAN_DPCM_DECODER) += dpcm.o
OBJS-$(CONFIG_XAN_WC3_DECODER) += xan.o
OBJS-$(CONFIG_XAN_WC4_DECODER) += xxan.o
OBJS-$(CONFIG_XBIN_DECODER) += bintext.o cga_data.o
+OBJS-$(CONFIG_XBM_DECODER) += xbmdec.o
OBJS-$(CONFIG_XBM_ENCODER) += xbmenc.o
OBJS-$(CONFIG_XL_DECODER) += xl.o
OBJS-$(CONFIG_XSUB_DECODER) += xsubdec.o
diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
index 5e3024d..4fea228 100644
--- a/libavcodec/allcodecs.c
+++ b/libavcodec/allcodecs.c
@@ -249,7 +249,7 @@ void avcodec_register_all(void)
REGISTER_DECODER (WNV1, wnv1);
REGISTER_DECODER (XAN_WC3, xan_wc3);
REGISTER_DECODER (XAN_WC4, xan_wc4);
- REGISTER_ENCODER (XBM, xbm);
+ REGISTER_ENCDEC (XBM, xbm);
REGISTER_DECODER (XL, xl);
REGISTER_ENCDEC (XWD, xwd);
REGISTER_ENCDEC (Y41P, y41p);
diff --git a/libavcodec/xbmdec.c b/libavcodec/xbmdec.c
new file mode 100644
index 0000000..cc0d6c9
--- /dev/null
+++ b/libavcodec/xbmdec.c
@@ -0,0 +1,130 @@
+/*
+ * 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 "internal.h"
+
+static av_cold int xbm_decode_init(AVCodecContext *avctx)
+{
+ avctx->coded_frame = avcodec_alloc_frame();
+ if (!avctx->coded_frame)
+ return AVERROR(ENOMEM);
+
+ return 0;
+}
+
+static int convert(uint8_t x)
+{
+ if (x >= 'a')
+ x -= 87;
+ else if (x >= 'A')
+ x -= 55;
+ else
+ x -= '0';
+ return x;
+}
+
+static int xbm_decode_frame(AVCodecContext *avctx, void *data,
+ int *data_size, AVPacket *avpkt)
+{
+ AVFrame *p = avctx->coded_frame;
+ const uint8_t *end, *ptr = avpkt->data;
+ uint8_t *dst;
+ int ret, linesize, i, j;
+
+ end = avpkt->data + avpkt->size;
+ while (!avctx->width || !avctx->height) {
+ char name[256];
+ int number, len;
+
+ ptr += strcspn(ptr, "#");
+ if (sscanf(ptr, "#define %256s %u", name, &number) != 2)
+ return AVERROR_INVALIDDATA;
+
+ len = strlen(name);
+ if ((len > 6) && !avctx->height && !memcmp(name + len - 7, "_height", 7)) {
+ avctx->height = number;
+ } else if ((len > 5) && !avctx->width && !memcmp(name + len - 6, "_width", 6)) {
+ avctx->width = number;
+ } else {
+ return AVERROR_INVALIDDATA;
+ }
+ ptr += strcspn(ptr, "\n\r") + 1;
+ }
+
+ avctx->pix_fmt = PIX_FMT_MONOWHITE;
+
+ if (p->data[0])
+ avctx->release_buffer(avctx, p);
+
+ p->reference = 0;
+ if ((ret = avctx->get_buffer(avctx, p)) < 0)
+ return ret;
+
+ linesize = (avctx->width + 7) / 8;
+ for (i = 0; i < avctx->height; i++) {
+ dst = p->data[0] + i * p->linesize[0];
+ for (j = 0; j < linesize; j++) {
+ uint8_t val;
+
+ ptr += strcspn(ptr, "x") + 1;
+ if (ptr < end && isxdigit(*ptr)) {
+ val = convert(*ptr);
+ ptr++;
+ if (isxdigit(*ptr))
+ val = (val << 4) + convert(*ptr);
+ *dst++ = av_reverse[val];
+ } else {
+ return AVERROR_INVALIDDATA;
+ }
+ }
+ }
+
+ p->key_frame = 1;
+ p->pict_type = AV_PICTURE_TYPE_I;
+
+ *data_size = sizeof(AVFrame);
+ *(AVFrame *)data = *p;
+
+ return avpkt->size;
+}
+
+static av_cold int xbm_decode_close(AVCodecContext *avctx)
+{
+ if (avctx->coded_frame->data[0])
+ avctx->release_buffer(avctx, avctx->coded_frame);
+
+ av_freep(&avctx->coded_frame);
+
+ return 0;
+}
+
+AVCodec ff_xbm_decoder = {
+ .name = "xbm",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .id = CODEC_ID_XBM,
+ .init = xbm_decode_init,
+ .close = xbm_decode_close,
+ .decode = xbm_decode_frame,
+ .capabilities = CODEC_CAP_DR1,
+ .long_name = NULL_IF_CONFIG_SMALL("XBM (X BitMap) image"),
+};
--
1.7.7
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