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Diffstat (limited to 'libavcodec/bmp_parser.c')
-rw-r--r--libavcodec/bmp_parser.c91
1 files changed, 91 insertions, 0 deletions
diff --git a/libavcodec/bmp_parser.c b/libavcodec/bmp_parser.c
new file mode 100644
index 0000000000..06ed367b38
--- /dev/null
+++ b/libavcodec/bmp_parser.c
@@ -0,0 +1,91 @@
+/*
+ * BMP parser
+ * 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
+ */
+
+/**
+ * @file
+ * BMP parser
+ */
+
+#include "libavutil/bswap.h"
+#include "parser.h"
+
+typedef struct BMPParseContext {
+ ParseContext pc;
+ uint32_t fsize;
+ uint32_t remaining_size;
+} BMPParseContext;
+
+static int bmp_parse(AVCodecParserContext *s, AVCodecContext *avctx,
+ const uint8_t **poutbuf, int *poutbuf_size,
+ const uint8_t *buf, int buf_size)
+{
+ BMPParseContext *bpc = s->priv_data;
+ uint64_t state = bpc->pc.state64;
+ int next = END_NOT_FOUND;
+ int i = 0;
+
+ s->pict_type = AV_PICTURE_TYPE_NONE;
+
+ *poutbuf_size = 0;
+ if (buf_size == 0)
+ return 0;
+
+ if (!bpc->pc.frame_start_found) {
+ for (; i < buf_size; i++) {
+ state = (state << 8) | buf[i];
+ if ((state >> 48) == (('B' << 8) | 'M')) {
+ bpc->fsize = av_bswap32(state >> 16);
+ bpc->pc.frame_start_found = 1;
+ if (bpc->fsize > buf_size - i + 7)
+ bpc->remaining_size = bpc->fsize - buf_size + i - 7;
+ else
+ next = bpc->fsize + i - 7;
+ break;
+ }
+ }
+ bpc->pc.state64 = state;
+ } else {
+ if (bpc->remaining_size) {
+ i = FFMIN(bpc->remaining_size, buf_size);
+ bpc->remaining_size -= i;
+ if (bpc->remaining_size)
+ goto flush;
+ next = i;
+ }
+ }
+
+flush:
+ if (ff_combine_frame(&bpc->pc, next, &buf, &buf_size) < 0)
+ return buf_size;
+
+ bpc->pc.frame_start_found = 0;
+
+ *poutbuf = buf;
+ *poutbuf_size = buf_size;
+ return next;
+}
+
+AVCodecParser ff_bmp_parser = {
+ .codec_ids = { AV_CODEC_ID_BMP },
+ .priv_data_size = sizeof(BMPParseContext),
+ .parser_parse = bmp_parse,
+ .parser_close = ff_parse_close,
+};