avcodec/tiff: Refactor TIFF tag related functions to share the code.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/Makefile

@@ -426,7 +426,7 @@ OBJS-$(CONFIG_TARGA_Y216_DECODER)      += targa_y216dec.o
 OBJS-$(CONFIG_THEORA_DECODER)          += xiph.o
 OBJS-$(CONFIG_THP_DECODER)             += mjpegdec.o mjpeg.o
 OBJS-$(CONFIG_TIERTEXSEQVIDEO_DECODER) += tiertexseqv.o
-OBJS-$(CONFIG_TIFF_DECODER)            += tiff.o lzw.o faxcompr.o tiff_data.o
+OBJS-$(CONFIG_TIFF_DECODER)            += tiff.o lzw.o faxcompr.o tiff_data.o tiff_common.o
 OBJS-$(CONFIG_TIFF_ENCODER)            += tiffenc.o rle.o lzwenc.o tiff_data.o
 OBJS-$(CONFIG_TMV_DECODER)             += tmv.o cga_data.o
 OBJS-$(CONFIG_TRUEHD_DECODER)          += mlpdec.o mlpdsp.o

libavcodec/tiff.h

@@ -31,6 +31,7 @@
 #define AVCODEC_TIFF_H
 
 #include <stdint.h>
+#include "tiff_common.h"
 
 /** abridged list of TIFF tags */
 enum TiffTags {
@@ -97,22 +98,6 @@ enum TiffCompr {
     TIFF_DEFLATE  = 0x80B2
 };
 
-enum TiffTypes {
-    TIFF_BYTE = 1,
-    TIFF_STRING,
-    TIFF_SHORT,
-    TIFF_LONG,
-    TIFF_RATIONAL,
-    TIFF_SBYTE,
-    TIFF_UNDEFINED,
-    TIFF_SSHORT,
-    TIFF_SLONG,
-    TIFF_SRATIONAL,
-    TIFF_FLOAT,
-    TIFF_DOUBLE,
-    TIFF_IFD
-};
-
 enum TiffGeoTagKey {
     TIFF_GT_MODEL_TYPE_GEOKEY                = 1024,
     TIFF_GT_RASTER_TYPE_GEOKEY               = 1025,
@@ -167,11 +152,6 @@ enum TiffGeoTagType {
     GEOTIFF_STRING = 34737
 };
 
-/** sizes of various TIFF field types (string size = 100)*/
-static const uint8_t type_sizes[14] = {
-    0, 1, 100, 2, 4, 8, 1, 1, 2, 4, 8, 4, 8, 4
-};
-
 typedef struct TiffGeoTag {
     enum TiffGeoTagKey key;
     enum TiffTags type;

libavcodec/tiff_common.c

+/*
+ * TIFF Common Routines
+ * Copyright (c) 2013 Thilo Borgmann <thilo.borgmann _at_ googlemail.com>
+ *
+ * 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
+ * TIFF Common Routines
+ * @author Thilo Borgmann <thilo.borgmann _at_ googlemail.com>
+ */
+
+#include "tiff_common.h"
+
+
+int ff_tis_ifd(unsigned tag)
+{
+    int i;
+    for (i = 0; i < FF_ARRAY_ELEMS(ifd_tags); i++) {
+        if (ifd_tags[i] == tag) {
+            return i + 1;
+        }
+    }
+    return 0;
+}
+
+
+unsigned ff_tget_short(GetByteContext *gb, int le)
+{
+    unsigned v = le ? bytestream2_get_le16(gb) : bytestream2_get_be16(gb);
+    return v;
+}
+
+
+unsigned ff_tget_long(GetByteContext *gb, int le)
+{
+    unsigned v = le ? bytestream2_get_le32(gb) : bytestream2_get_be32(gb);
+    return v;
+}
+
+
+double ff_tget_double(GetByteContext *gb, int le)
+{
+    av_alias64 i = { .u64 = le ? bytestream2_get_le64(gb) : bytestream2_get_be64(gb)};
+    return i.f64;
+}
+
+
+unsigned ff_tget(GetByteContext *gb, int type, int le)
+{
+    switch (type) {
+    case TIFF_BYTE:
+        return bytestream2_get_byte(gb);
+    case TIFF_SHORT:
+        return ff_tget_short(gb, le);
+    case TIFF_LONG:
+        return ff_tget_long(gb, le);
+    default:
+        return UINT_MAX;
+    }
+}
+
+
+int ff_tadd_rational_metadata(int count, const char *name, const char *sep,
+                              GetByteContext *gb, int le, AVDictionary **metadata)
+{
+    AVBPrint bp;
+    char *ap;
+    int32_t nom, denom;
+    int i;
+
+    if (count >= INT_MAX / sizeof(int64_t) || count <= 0)
+        return AVERROR_INVALIDDATA;
+    if (bytestream2_get_bytes_left(gb) < count * sizeof(int64_t))
+        return AVERROR_INVALIDDATA;
+    if (!sep) sep = ", ";
+
+    av_bprint_init(&bp, 10 * count, AV_BPRINT_SIZE_AUTOMATIC);
+
+    for (i = 0; i < count; i++) {
+        nom   = ff_tget_long(gb, le);
+        denom = ff_tget_long(gb, le);
+        av_bprintf(&bp, "%s%i:%i", (i ? sep : ""), nom, denom);
+    }
+
+    if ((i = av_bprint_finalize(&bp, &ap))) {
+        return i;
+    }
+    if (!ap) {
+        return AVERROR(ENOMEM);
+    }
+
+    av_dict_set(metadata, name, ap, AV_DICT_DONT_STRDUP_VAL);
+
+    return 0;
+}
+
+
+int ff_tadd_long_metadata(int count, const char *name, const char *sep,
+                          GetByteContext *gb, int le, AVDictionary **metadata)
+{
+    AVBPrint bp;
+    char *ap;
+    int i;
+
+    if (count >= INT_MAX / sizeof(int32_t) || count <= 0)
+        return AVERROR_INVALIDDATA;
+    if (bytestream2_get_bytes_left(gb) < count * sizeof(int32_t))
+        return AVERROR_INVALIDDATA;
+    if (!sep) sep = ", ";
+
+    av_bprint_init(&bp, 10 * count, AV_BPRINT_SIZE_AUTOMATIC);
+
+    for (i = 0; i < count; i++) {
+        av_bprintf(&bp, "%s%i", (i ? sep : ""), ff_tget_long(gb, le));
+    }
+
+    if ((i = av_bprint_finalize(&bp, &ap))) {
+        return i;
+    }
+    if (!ap) {
+        return AVERROR(ENOMEM);
+    }
+
+    av_dict_set(metadata, name, ap, AV_DICT_DONT_STRDUP_VAL);
+
+    return 0;
+}
+
+
+int ff_tadd_doubles_metadata(int count, const char *name, const char *sep,
+                             GetByteContext *gb, int le, AVDictionary **metadata)
+{
+    AVBPrint bp;
+    char *ap;
+    int i;
+
+    if (count >= INT_MAX / sizeof(int64_t) || count <= 0)
+        return AVERROR_INVALIDDATA;
+    if (bytestream2_get_bytes_left(gb) < count * sizeof(int64_t))
+        return AVERROR_INVALIDDATA;
+    if (!sep) sep = ", ";
+
+    av_bprint_init(&bp, 10 * count, AV_BPRINT_SIZE_AUTOMATIC);
+
+    for (i = 0; i < count; i++) {
+        av_bprintf(&bp, "%s%f", (i ? sep : ""), ff_tget_double(gb, le));
+    }
+
+    if ((i = av_bprint_finalize(&bp, &ap))) {
+        return i;
+    }
+    if (!ap) {
+        return AVERROR(ENOMEM);
+    }
+
+    av_dict_set(metadata, name, ap, AV_DICT_DONT_STRDUP_VAL);
+
+    return 0;
+}
+
+
+int ff_tadd_shorts_metadata(int count, const char *name, const char *sep,
+                            GetByteContext *gb, int le, AVDictionary **metadata)
+{
+    AVBPrint bp;
+    char *ap;
+    int i;
+
+    if (count >= INT_MAX / sizeof(int16_t) || count <= 0)
+        return AVERROR_INVALIDDATA;
+    if (bytestream2_get_bytes_left(gb) < count * sizeof(int16_t))
+        return AVERROR_INVALIDDATA;
+    if (!sep) sep = ", ";
+
+    av_bprint_init(&bp, 10 * count, AV_BPRINT_SIZE_AUTOMATIC);
+
+    for (i = 0; i < count; i++) {
+        av_bprintf(&bp, "%s%i", (i ? sep : ""), ff_tget_short(gb, le));
+    }
+
+    if ((i = av_bprint_finalize(&bp, &ap))) {
+        return i;
+    }
+    if (!ap) {
+        return AVERROR(ENOMEM);
+    }
+
+    av_dict_set(metadata, name, ap, AV_DICT_DONT_STRDUP_VAL);
+
+    return 0;
+}
+
+
+int ff_tadd_string_metadata(int count, const char *name,
+                            GetByteContext *gb, int le, AVDictionary **metadata)
+{
+    char *value;
+
+    if (bytestream2_get_bytes_left(gb) < count || count < 0)
+        return AVERROR_INVALIDDATA;
+
+    value = av_malloc(count + 1);
+    if (!value)
+        return AVERROR(ENOMEM);
+
+    bytestream2_get_bufferu(gb, value, count);
+    value[count] = 0;
+
+    av_dict_set(metadata, name, value, AV_DICT_DONT_STRDUP_VAL);
+    return 0;
+}
+
+
+int ff_tdecode_header(GetByteContext *gb, int *le, int *ifd_offset)
+{
+    if (bytestream2_get_bytes_left(gb) < 8) {
+        return AVERROR_INVALIDDATA;
+    }
+
+    *le = bytestream2_get_le16u(gb);
+    if (*le == AV_RB16("II")) {
+        *le = 1;
+    } else if (*le == AV_RB16("MM")) {
+        *le = 0;
+    } else {
+        return AVERROR_INVALIDDATA;
+    }
+
+    if (ff_tget_short(gb, *le) != 42) {
+        return AVERROR_INVALIDDATA;
+    }
+
+    *ifd_offset = ff_tget_long(gb, *le);
+
+    return 0;
+}
+
+
+int ff_tread_tag(GetByteContext *gb, int le, unsigned *tag, unsigned *type,
+                 unsigned *count, int *next)
+{
+    int ifd_tag;
+    int valid_type;
+
+    *tag    = ff_tget_short(gb, le);
+    *type   = ff_tget_short(gb, le);
+    *count  = ff_tget_long (gb, le);
+
+    ifd_tag    = ff_tis_ifd(*tag);
+    valid_type = *type != 0 && *type < FF_ARRAY_ELEMS(type_sizes);
+
+    *next = bytestream2_tell(gb) + 4;
+
+    // check for valid type
+    if (!valid_type) {
+        return AVERROR_INVALIDDATA;
+    }
+
+    // seek to offset if this is an IFD-tag or
+    // if count values do not fit into the offset value
+    if (ifd_tag || (*count > 4 || !(type_sizes[*type] * (*count) <= 4 || *type == TIFF_STRING))) {
+        bytestream2_seek(gb, ff_tget_long (gb, le), SEEK_SET);
+    }
+
+    return 0;
+}

libavcodec/tiff_common.h

+/*
+ * TIFF Common Routines
+ * Copyright (c) 2013 Thilo Borgmann <thilo.borgmann _at_ googlemail.com>
+ *
+ * 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
+ * TIFF Common Routines
+ * @author Thilo Borgmann <thilo.borgmann _at_ googlemail.com>
+ */
+
+#ifndef AVCODEC_TIFF_COMMON_H
+#define AVCODEC_TIFF_COMMON_H
+
+#include "avcodec.h"
+#include "tiff.h"
+#include "bytestream.h"
+#include "libavutil/bprint.h"
+
+/** data type identifiers for TIFF tags */
+enum TiffTypes {
+    TIFF_BYTE = 1,
+    TIFF_STRING,
+    TIFF_SHORT,
+    TIFF_LONG,
+    TIFF_RATIONAL,
+    TIFF_SBYTE,
+    TIFF_UNDEFINED,
+    TIFF_SSHORT,
+    TIFF_SLONG,
+    TIFF_SRATIONAL,
+    TIFF_FLOAT,
+    TIFF_DOUBLE,
+    TIFF_IFD
+};
+
+/** sizes of various TIFF field types (string size = 100)*/
+static const uint8_t type_sizes[14] = {
+    0, 1, 100, 2, 4, 8, 1, 1, 2, 4, 8, 4, 8, 4
+};
+
+static const uint16_t ifd_tags[] = {
+    0x8769, // EXIF IFD
+    0x8825, // GPS IFD
+    0xA005  // Interoperability IFD
+};
+
+
+/** Returns a value > 0 if the tag is a known IFD-tag.
+ *  The return value is the array index + 1 within ifd_tags[].
+ */
+int ff_tis_ifd(unsigned tag);
+
+/** Reads a short from the bytestream using given endianess. */
+unsigned ff_tget_short(GetByteContext *gb, int le);
+
+/** Reads a long from the bytestream using given endianess. */
+unsigned ff_tget_long(GetByteContext *gb, int le);
+
+/** Reads a double from the bytestream using given endianess. */
+double   ff_tget_double(GetByteContext *gb, int le);
+
+/** Reads a byte from the bytestream using given endianess. */
+unsigned ff_tget(GetByteContext *gb, int type, int le);
+
+/** Returns an allocated string containing count
+ *  rational values using the given seperator.
+ */
+char *ff_trationals2str(int *rp, int count, const char *sep);
+
+/** Returns an allocated string containing count
+ *  long values using the given seperator.
+ */
+char *ff_tlongs2str(int32_t *lp, int count, const char *sep);
+
+/** Returns an allocated string containing count
+ *  double values using the given seperator.
+ */
+char *ff_tdoubles2str(double *dp, int count, const char *sep);
+
+/** Returns an allocated string containing count
+ *  short values using the given seperator.
+ */
+char *ff_tshorts2str(int16_t *sp, int count, const char *sep);
+
+/** Adds count rationals converted to a string
+ *  into the metadata dictionary.
+ */
+int ff_tadd_rational_metadata(int count, const char *name, const char *sep,
+                              GetByteContext *gb, int le, AVDictionary **metadata);
+
+/** Adds count longs converted to a string
+ *  into the metadata dictionary.
+ */
+int ff_tadd_long_metadata(int count, const char *name, const char *sep,
+                          GetByteContext *gb, int le, AVDictionary **metadata);
+
+/** Adds count doubles converted to a string
+ *  into the metadata dictionary.
+ */
+int ff_tadd_doubles_metadata(int count, const char *name, const char *sep,
+                             GetByteContext *gb, int le, AVDictionary **metadata);
+
+/** Adds count shorts converted to a string
+ *  into the metadata dictionary.
+ */
+int ff_tadd_shorts_metadata(int count, const char *name, const char *sep,
+                            GetByteContext *gb, int le, AVDictionary **metadata);
+
+/** Adds a string of count characters
+ *  into the metadata dictionary.
+ */
+int ff_tadd_string_metadata(int count, const char *name,
+                            GetByteContext *gb, int le, AVDictionary **metadata);
+
+/** Decodes a TIFF header from the input bytestream
+ *  and sets the endianess in *le and the offset to
+ *  the first IFD in *ifd_offset accordingly.
+ */
+int ff_tdecode_header(GetByteContext *gb, int *le, int *ifd_offset);
+
+/** Reads the first 3 fields of a TIFF tag, which are
+ *  the tag id, the tag type and the count of values for that tag.
+ *  Afterwards the bytestream is located at the first value to read and
+ *  *next holds the bytestream offset of the following tag.
+ */
+int ff_tread_tag(GetByteContext *gb, int le, unsigned *tag, unsigned *type,
+                 unsigned *count, int *next);
+
+#endif /* AVCODEC_TIFF_COMMON_H */