* [FFmpeg-devel] [PATCH] libavutil: add qtff well-known type functions (PR #20846)
@ 2025-11-05 19:37 Lukas via ffmpeg-devel
2025-11-05 21:02 ` [FFmpeg-devel] " Kieran Kunhya via ffmpeg-devel
0 siblings, 1 reply; 2+ messages in thread
From: Lukas via ffmpeg-devel @ 2025-11-05 19:37 UTC (permalink / raw)
To: ffmpeg-devel; +Cc: Lukas
PR #20846 opened by Lukas (lholliger)
URL: https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/20846
Patch URL: https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/20846.patch
QuickTime File Format (QTFF/MOV) have a list of well-known datatypes
and there is currently little in place to decode or encode these
values besides a small part in mov.c. This adds the ability to encode
and decode various types for integers, floats, and strings. These
well-known types have usage to decoding some parts on the moov atom
or for metadata boxed/mebx values.
Also updated mov.c to use this function.
>From 9a4c805ea90401f8c51f31be1c4c523815dfa100 Mon Sep 17 00:00:00 2001
From: lholliger <lukas@holliger.me>
Date: Wed, 5 Nov 2025 14:15:08 -0500
Subject: [PATCH 1/2] libavutil: add qtff well-known type functions
QuickTime File Format (QTFF/MOV) have a list of well-known datatypes
and there is currently little in place to decode or encode these
values besides a small part in mov.c. This adds the ability to encode
and decode various types for integers, floats, and strings. These
well-known types have usage to decoding some parts on the moov atom
or for metadata boxed/mebx values.
Signed-off-by: lholliger <lukas@holliger.me>
---
libavutil/Makefile | 2 +
libavutil/qtff.c | 380 +++++++++++++++++++++++++++++++++++++++++++++
libavutil/qtff.h | 59 +++++++
3 files changed, 441 insertions(+)
create mode 100644 libavutil/qtff.c
create mode 100644 libavutil/qtff.h
diff --git a/libavutil/Makefile b/libavutil/Makefile
index ee77e51c08..792b587529 100644
--- a/libavutil/Makefile
+++ b/libavutil/Makefile
@@ -75,6 +75,7 @@ HEADERS = adler32.h \
pixdesc.h \
pixelutils.h \
pixfmt.h \
+ qtff.h \
random_seed.h \
rc4.h \
rational.h \
@@ -168,6 +169,7 @@ OBJS = adler32.o \
parseutils.o \
pixdesc.o \
pixelutils.o \
+ qtff.o \
random_seed.o \
rational.o \
refstruct.o \
diff --git a/libavutil/qtff.c b/libavutil/qtff.c
new file mode 100644
index 0000000000..a58d360958
--- /dev/null
+++ b/libavutil/qtff.c
@@ -0,0 +1,380 @@
+/*
+ * copyright (c) 2025 Lukas Holliger
+ *
+ * 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 <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "qtff.h"
+#include "intfloat.h"
+#include "intreadwrite.h"
+#include "error.h"
+
+int av_qtff_convert_well_known_to_str(int data_type, const uint8_t *data, int data_size,
+ char *str, int str_size)
+{
+ if (!data || !str || str_size <= 0)
+ return AVERROR(EINVAL);
+
+ switch (data_type) {
+ case 0: // Reserved
+ case 2: // UTF-16
+ case 3: // S/JIS
+ case 4: // UTF-8 sort
+ case 5: // UTF-16 sort
+ case 13: // JPEG
+ case 14: // PNG
+ case 27: // BMP
+ case 28: // QuickTime Metadata atom
+ case 70: // BE PointF32
+ case 71: // BE DimensionsF32
+ case 72: // BE RectF32
+ case 79: // AffineTransformF64
+ return AVERROR_PATCHWELCOME;
+ case 1: { // UTF-8
+ int len = data_size < str_size - 1 ? data_size : str_size - 1;
+ memcpy(str, data, len);
+ str[len] = '\0';
+ break;
+ }
+ case 21: { // BE Signed Integer (variable size, not usable for timed metadata)
+ int val = 0;
+ switch (data_size) {
+ case 1:
+ val = (int8_t)AV_RB8(data);
+ break;
+ case 2:
+ val = (int16_t)AV_RB16(data);
+ break;
+ case 3:
+ val = ((int32_t)(AV_RB24(data) << 8)) >> 8;
+ break;
+ case 4:
+ val = (int32_t)AV_RB32(data);
+ break;
+ default:
+ return AVERROR(EINVAL);
+ }
+
+ if (snprintf(str, str_size, "%d", val) >= str_size)
+ return AVERROR(ENOMEM);
+ break;
+ }
+ case 22: { // BE Unsigned Integer (variable size, not usable for timed metadata)
+ unsigned int val = 0;
+ switch (data_size) {
+ case 1:
+ val = AV_RB8(data);
+ break;
+ case 2:
+ val = AV_RB16(data);
+ break;
+ case 3:
+ val = AV_RB24(data);
+ break;
+ case 4:
+ val = AV_RB32(data);
+ break;
+ default:
+ return AVERROR(EINVAL);
+ }
+
+ if (snprintf(str, str_size, "%u", val) >= str_size)
+ return AVERROR(ENOMEM);
+ break;
+ }
+ case 23: { // BE float32
+ float val;
+ if (data_size != 4)
+ return AVERROR(EINVAL);
+
+ val = av_int2float(AV_RB32(data));
+ if (snprintf(str, str_size, "%f", val) >= str_size)
+ return AVERROR(ENOMEM);
+ break;
+ }
+ case 24: { // BE float64
+ double val;
+ if (data_size != 8)
+ return AVERROR(EINVAL);
+
+ val = av_int2double(AV_RB64(data));
+ if (snprintf(str, str_size, "%f", val) >= str_size)
+ return AVERROR(ENOMEM);
+ break;
+ }
+ case 65: // 8-bit Signed Integer
+ if (data_size != 1)
+ return AVERROR(EINVAL);
+ if (snprintf(str, str_size, "%d", (int)(int8_t)data[0]) >= str_size)
+ return AVERROR(ENOMEM);
+ break;
+ case 66: // BE 16-bit Signed Integer
+ if (data_size != 2)
+ return AVERROR(EINVAL);
+ if (snprintf(str, str_size, "%d", (int)(int16_t)AV_RB16(data)) >= str_size)
+ return AVERROR(ENOMEM);
+ break;
+ case 67: // BE 32-bit Signed Integer
+ if (data_size != 4)
+ return AVERROR(EINVAL);
+ if (snprintf(str, str_size, "%d", (int)(int32_t)AV_RB32(data)) >= str_size)
+ return AVERROR(ENOMEM);
+ break;
+ case 74: // BE 64-bit Signed Integer
+ if (data_size != 8)
+ return AVERROR(EINVAL);
+ if (snprintf(str, str_size, "%lld", (long long)(int64_t)AV_RB64(data)) >= str_size)
+ return AVERROR(ENOMEM);
+ break;
+ case 75: // 8-bit Unsigned Integer
+ if (data_size != 1)
+ return AVERROR(EINVAL);
+ if (snprintf(str, str_size, "%u", (unsigned int)data[0]) >= str_size)
+ return AVERROR(ENOMEM);
+ break;
+ case 76: // BE 16-bit Unsigned Integer
+ if (data_size != 2)
+ return AVERROR(EINVAL);
+ if (snprintf(str, str_size, "%u", (unsigned int)AV_RB16(data)) >= str_size)
+ return AVERROR(ENOMEM);
+ break;
+ case 77: // BE 32-bit Unsigned Integer
+ if (data_size != 4)
+ return AVERROR(EINVAL);
+ if (snprintf(str, str_size, "%u", (unsigned int)AV_RB32(data)) >= str_size)
+ return AVERROR(ENOMEM);
+ break;
+ case 78: // BE 64-bit Unsigned Integer
+ if (data_size != 8)
+ return AVERROR(EINVAL);
+ if (snprintf(str, str_size, "%llu", (unsigned long long)AV_RB64(data)) >= str_size)
+ return AVERROR(ENOMEM);
+ break;
+ default:
+ return AVERROR(EINVAL);
+ }
+
+ return 0;
+}
+
+int av_qtff_convert_str_to_well_known(int data_type, const char *str, uint8_t *data, int data_size)
+{
+ if (!str || !data)
+ return AVERROR(EINVAL);
+
+ switch (data_type) {
+ case 0: // Reserved
+ case 2: // UTF-16
+ case 3: // S/JIS
+ case 4: // UTF-8 sort
+ case 5: // UTF-16 sort
+ case 13: // JPEG
+ case 14: // PNG
+ case 27: // BMP
+ case 28: // QuickTime Metadata atom
+ case 70: // BE PointF32
+ case 71: // BE DimensionsF32
+ case 72: // BE RectF32
+ case 79: // AffineTransformF64
+ return AVERROR_PATCHWELCOME; // these are defined well-known types, but not implemented to be parsed
+ case 1: { // UTF-8
+ int len = strlen(str);
+ if (len > data_size)
+ return AVERROR(ENOMEM);
+ memcpy(data, str, len);
+ return len;
+ }
+ case 21: { // BE Signed Integer (variable size, not usable for timed metadata)
+ long long val;
+ char *endptr;
+
+ val = strtoll(str, &endptr, 10);
+ if (endptr == str || *endptr != '\0')
+ return AVERROR(EINVAL);
+
+ switch (data_size) {
+ case 1:
+ if (val < INT8_MIN || val > INT8_MAX)
+ return AVERROR(ERANGE);
+ AV_WB8(data, (uint8_t)val);
+ break;
+ case 2:
+ if (val < INT16_MIN || val > INT16_MAX)
+ return AVERROR(ERANGE);
+ AV_WB16(data, (int16_t)val);
+ break;
+ case 3:
+ if (val < -8388608 || val > 8388607) // 24-bit signed range
+ return AVERROR(ERANGE);
+ AV_WB24(data, (int32_t)val);
+ break;
+ case 4:
+ if (val < INT32_MIN || val > INT32_MAX)
+ return AVERROR(ERANGE);
+ AV_WB32(data, (int32_t)val);
+ break;
+ default:
+ return AVERROR(EINVAL);
+ }
+ break;
+ }
+ case 22: { // BE unsigned integer, variable size
+ unsigned long long val;
+ char *endptr;
+
+ val = strtoull(str, &endptr, 10);
+ if (endptr == str || *endptr != '\0')
+ return AVERROR(EINVAL);
+
+ switch (data_size) {
+ case 1:
+ if (val > UINT8_MAX)
+ return AVERROR(ERANGE);
+ AV_WB8(data, (uint8_t)val);
+ break;
+ case 2:
+ if (val > UINT16_MAX)
+ return AVERROR(ERANGE);
+ AV_WB16(data, (uint16_t)val);
+ break;
+ case 3:
+ if (val > 16777215) // 24-bit unsigned range
+ return AVERROR(ERANGE);
+ AV_WB24(data, (uint32_t)val);
+ break;
+ case 4:
+ if (val > UINT32_MAX)
+ return AVERROR(ERANGE);
+ AV_WB32(data, (uint32_t)val);
+ break;
+ default:
+ return AVERROR(EINVAL);
+ }
+ break;
+ }
+ case 23: { // BE float32
+ float val;
+ char *endptr;
+
+ if (data_size != 4)
+ return AVERROR(EINVAL);
+
+ val = strtof(str, &endptr);
+ if (endptr == str || *endptr != '\0')
+ return AVERROR(EINVAL);
+
+ AV_WB32(data, av_float2int(val));
+ break;
+ }
+ case 24: { // BE float64
+ double val;
+ char *endptr;
+
+ if (data_size != 8)
+ return AVERROR(EINVAL);
+
+ val = strtod(str, &endptr);
+ if (endptr == str || *endptr != '\0')
+ return AVERROR(EINVAL);
+
+ AV_WB64(data, av_double2int(val));
+ break;
+ }
+ case 65: // 8-bit Signed Integer
+ case 66: // BE 16-bit Signed Integer
+ case 67: // BE 32-bit Signed Integer
+ case 74: { // BE 64-bit Signed Integer
+ long long val;
+ char *endptr;
+ int expected_size = (data_type == 65) ? 1 : (data_type == 66) ? 2 : (data_type == 67) ? 4 : 8;
+
+ if (data_size != expected_size)
+ return AVERROR(EINVAL);
+
+ val = strtoll(str, &endptr, 10);
+ if (endptr == str || *endptr != '\0')
+ return AVERROR(EINVAL);
+
+ switch (data_type) {
+ case 65:
+ if (val < INT8_MIN || val > INT8_MAX)
+ return AVERROR(ERANGE);
+ AV_WB8(data, (uint8_t)val);
+ break;
+ case 66:
+ if (val < INT16_MIN || val > INT16_MAX)
+ return AVERROR(ERANGE);
+ AV_WB16(data, (int16_t)val);
+ break;
+ case 67:
+ if (val < INT32_MIN || val > INT32_MAX)
+ return AVERROR(ERANGE);
+ AV_WB32(data, (int32_t)val);
+ break;
+ case 74:
+ AV_WB64(data, (int64_t)val);
+ break;
+ }
+ break;
+ }
+ case 75: // 8-bit Unsigned Integer
+ case 76: // BE 16-bit Unsigned Integer
+ case 77: // BE 32-bit Unsigned Integer
+ case 78: { // BE 64-bit Unsigned Integer
+ unsigned long long val;
+ char *endptr;
+ int expected_size = (data_type == 75) ? 1 : (data_type == 76) ? 2 : (data_type == 77) ? 4 : 8;
+
+ if (data_size != expected_size)
+ return AVERROR(EINVAL);
+
+ val = strtoull(str, &endptr, 10);
+ if (endptr == str || *endptr != '\0')
+ return AVERROR(EINVAL);
+
+ switch (data_type) {
+ case 75:
+ if (val > UINT8_MAX)
+ return AVERROR(ERANGE);
+ AV_WB8(data, (uint8_t)val);
+ break;
+ case 76:
+ if (val > UINT16_MAX)
+ return AVERROR(ERANGE);
+ AV_WB16(data, (uint16_t)val);
+ break;
+ case 77:
+ if (val > UINT32_MAX)
+ return AVERROR(ERANGE);
+ AV_WB32(data, (uint32_t)val);
+ break;
+ case 78:
+ AV_WB64(data, (uint64_t)val);
+ break;
+ }
+ break;
+ }
+ default:
+ return AVERROR(EINVAL);
+ }
+
+ return data_size;
+}
diff --git a/libavutil/qtff.h b/libavutil/qtff.h
new file mode 100644
index 0000000000..912ea9e870
--- /dev/null
+++ b/libavutil/qtff.h
@@ -0,0 +1,59 @@
+/*
+ * copyright (c) 2025 Lukas Holliger
+ *
+ * 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
+ */
+
+#ifndef AVUTIL_QTFF_H
+#define AVUTIL_QTFF_H
+
+#include <stdint.h>
+
+/**
+ * @file
+ * QuickTime File Format (QTFF) utilities
+ */
+
+/**
+ * Convert a QuickTime well-known type to a string
+ *
+ * @param data_type QuickTime metadata data type
+ * @param data Pointer to the binary data
+ * @param data_size Size of the binary data in bytes
+ * @param str Buffer to write the string representation to
+ * @param str_size Size of the output buffer
+ * @return 0 on success, negative AVERROR code on failure
+ *
+ * @see https://developer.apple.com/documentation/quicktime-file-format/well-known_types
+ */
+int av_qtff_convert_well_known_to_str(int data_type, const uint8_t *data, int data_size,
+ char *str, int str_size);
+
+/**
+ * Convert a string to QuickTime well-known value
+ *
+ * @param data_type QuickTime metadata data type
+ * @param str Input string to convert
+ * @param data Buffer to write the binary data to
+ * @param data_size Size to use for the binary data
+ * @return Number of bytes written on success, negative AVERROR code on failure
+ *
+ * @see https://developer.apple.com/documentation/quicktime-file-format/well-known_types
+ */
+int av_qtff_convert_str_to_well_known(int data_type, const char *str, uint8_t *data, int data_size);
+
+#endif /* AVUTIL_QTFF_H */
--
2.49.1
>From 3616592b585440ca4984052e53c85ff5df29f3bf Mon Sep 17 00:00:00 2001
From: lholliger <lukas@holliger.me>
Date: Wed, 5 Nov 2025 14:33:22 -0500
Subject: [PATCH 2/2] libavformat/mov: use qtff decoder util
There was previously a segment here to attempt to decode some of the
well-known QTFF types but in order to simplify the function and
implement more types this segment can be replaced with a call to
the qtff util.
Signed-off-by: lholliger <lukas@holliger.me>
---
libavformat/mov.c | 78 +++++++++++++++++------------------------------
1 file changed, 28 insertions(+), 50 deletions(-)
diff --git a/libavformat/mov.c b/libavformat/mov.c
index 45c562cdc6..9cf62955c2 100644
--- a/libavformat/mov.c
+++ b/libavformat/mov.c
@@ -45,6 +45,7 @@
#include "libavutil/aes.h"
#include "libavutil/aes_ctr.h"
#include "libavutil/pixdesc.h"
+#include "libavutil/qtff.h"
#include "libavutil/sha.h"
#include "libavutil/spherical.h"
#include "libavutil/stereo3d.h"
@@ -521,61 +522,38 @@ retry:
else {
if (!raw && (data_type == 3 || (data_type == 0 && (langcode < 0x400 || langcode == 0x7fff)))) { // MAC Encoded
mov_read_mac_string(c, pb, str_size, str, str_size_alloc);
- } else if (data_type == 21) { // BE signed integer, variable size
- int val = 0;
- if (str_size == 1)
- val = (int8_t)avio_r8(pb);
- else if (str_size == 2)
- val = (int16_t)avio_rb16(pb);
- else if (str_size == 3)
- val = ((int32_t)(avio_rb24(pb)<<8))>>8;
- else if (str_size == 4)
- val = (int32_t)avio_rb32(pb);
- if (snprintf(str, str_size_alloc, "%d", val) >= str_size_alloc) {
- av_log(c->fc, AV_LOG_ERROR,
- "Failed to store the number (%d) in string.\n", val);
- av_free(str);
- return AVERROR_INVALIDDATA;
- }
- } else if (data_type == 22) { // BE unsigned integer, variable size
- unsigned int val = 0;
- if (str_size == 1)
- val = avio_r8(pb);
- else if (str_size == 2)
- val = avio_rb16(pb);
- else if (str_size == 3)
- val = avio_rb24(pb);
- else if (str_size == 4)
- val = avio_rb32(pb);
- if (snprintf(str, str_size_alloc, "%u", val) >= str_size_alloc) {
- av_log(c->fc, AV_LOG_ERROR,
- "Failed to store the number (%u) in string.\n", val);
- av_free(str);
- return AVERROR_INVALIDDATA;
- }
- } else if (data_type == 23 && str_size >= 4) { // BE float32
- float val = av_int2float(avio_rb32(pb));
- if (snprintf(str, str_size_alloc, "%f", val) >= str_size_alloc) {
- av_log(c->fc, AV_LOG_ERROR,
- "Failed to store the float32 number (%f) in string.\n", val);
- av_free(str);
- return AVERROR_INVALIDDATA;
- }
- } else if (data_type > 1 && data_type != 4) {
- // data_type can be 0 if not set at all above. data_type 1 means
- // UTF8 and 4 means "UTF8 sort". For any other type (UTF16 or e.g.
- // a picture), don't return it blindly in a string that is supposed
- // to be UTF8 text.
- av_log(c->fc, AV_LOG_WARNING, "Skipping unhandled metadata %s of type %d\n", key, data_type);
- av_free(str);
- return 0;
} else {
- int ret = ffio_read_size(pb, str, str_size);
+ uint8_t *data_buf = av_malloc(str_size);
+ int ret;
+
+ if (!data_buf) {
+ av_free(str);
+ return AVERROR(ENOMEM);
+ }
+
+ ret = ffio_read_size(pb, data_buf, str_size);
if (ret < 0) {
+ av_free(data_buf);
+ av_free(str);
+ return ret;
+ }
+
+ // Data types 0 and 4 are technically reserved and a special case, but were previously
+ // decoded to UTF-8 here.
+ ret = av_qtff_convert_well_known_to_str(data_type == 0 || data_type == 4 ? 1 : data_type,
+ data_buf, str_size, str, str_size_alloc);
+ av_free(data_buf);
+
+ if (ret == AVERROR_PATCHWELCOME || ret == AVERROR(EINVAL)) {
+ av_log(c->fc, AV_LOG_WARNING, "Skipping unhandled metadata %s of type %d\n", key, data_type);
+ av_free(str);
+ return 0;
+ } else if (ret < 0) {
+ av_log(c->fc, AV_LOG_ERROR,
+ "Failed to convert metadata %s of type %d to string.\n", key, data_type);
av_free(str);
return ret;
}
- str[str_size] = 0;
}
c->fc->event_flags |= AVFMT_EVENT_FLAG_METADATA_UPDATED;
av_dict_set(metadata, key, str, 0);
--
2.49.1
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^ permalink raw reply [flat|nested] 2+ messages in thread
* [FFmpeg-devel] Re: [PATCH] libavutil: add qtff well-known type functions (PR #20846)
2025-11-05 19:37 [FFmpeg-devel] [PATCH] libavutil: add qtff well-known type functions (PR #20846) Lukas via ffmpeg-devel
@ 2025-11-05 21:02 ` Kieran Kunhya via ffmpeg-devel
0 siblings, 0 replies; 2+ messages in thread
From: Kieran Kunhya via ffmpeg-devel @ 2025-11-05 21:02 UTC (permalink / raw)
To: FFmpeg development discussions and patches; +Cc: Lukas, Kieran Kunhya
On Wed, 5 Nov 2025, 20:37 Lukas via ffmpeg-devel, <ffmpeg-devel@ffmpeg.org>
wrote:
> PR #20846 opened by Lukas (lholliger)
> URL: https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/20846
> Patch URL: https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/20846.patch
>
> QuickTime File Format (QTFF/MOV) have a list of well-known datatypes
> and there is currently little in place to decode or encode these
> values besides a small part in mov.c. This adds the ability to encode
> and decode various types for integers, floats, and strings. These
> well-known types have usage to decoding some parts on the moov atom
> or for metadata boxed/mebx values.
>
> Also updated mov.c to use this function.
>
>
>
>
> >From 9a4c805ea90401f8c51f31be1c4c523815dfa100 Mon Sep 17 00:00:00 2001
> From: lholliger <lukas@holliger.me>
> Date: Wed, 5 Nov 2025 14:15:08 -0500
> Subject: [PATCH 1/2] libavutil: add qtff well-known type functions
>
> QuickTime File Format (QTFF/MOV) have a list of well-known datatypes
> and there is currently little in place to decode or encode these
> values besides a small part in mov.c. This adds the ability to encode
> and decode various types for integers, floats, and strings. These
> well-known types have usage to decoding some parts on the moov atom
> or for metadata boxed/mebx values.
>
> Signed-off-by: lholliger <lukas@holliger.me>
> ---
> libavutil/Makefile | 2 +
> libavutil/qtff.c | 380 +++++++++++++++++++++++++++++++++++++++++++++
> libavutil/qtff.h | 59 +++++++
> 3 files changed, 441 insertions(+)
> create mode 100644 libavutil/qtff.c
> create mode 100644 libavutil/qtff.h
>
> diff --git a/libavutil/Makefile b/libavutil/Makefile
> index ee77e51c08..792b587529 100644
> --- a/libavutil/Makefile
> +++ b/libavutil/Makefile
> @@ -75,6 +75,7 @@ HEADERS = adler32.h
> \
> pixdesc.h \
> pixelutils.h \
> pixfmt.h \
> + qtff.h \
> random_seed.h \
> rc4.h \
> rational.h \
> @@ -168,6 +169,7 @@ OBJS = adler32.o
> \
> parseutils.o \
> pixdesc.o \
> pixelutils.o \
> + qtff.o \
> random_seed.o \
> rational.o \
> refstruct.o \
> diff --git a/libavutil/qtff.c b/libavutil/qtff.c
> new file mode 100644
> index 0000000000..a58d360958
> --- /dev/null
> +++ b/libavutil/qtff.c
> @@ -0,0 +1,380 @@
> +/*
> + * copyright (c) 2025 Lukas Holliger
> + *
> + * 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 <stdio.h>
> +#include <stdlib.h>
> +#include <string.h>
> +
> +#include "qtff.h"
> +#include "intfloat.h"
> +#include "intreadwrite.h"
> +#include "error.h"
> +
> +int av_qtff_convert_well_known_to_str(int data_type, const uint8_t *data,
> int data_size,
> + char *str, int str_size)
> +{
> + if (!data || !str || str_size <= 0)
> + return AVERROR(EINVAL);
> +
> + switch (data_type) {
> + case 0: // Reserved
> + case 2: // UTF-16
> + case 3: // S/JIS
> + case 4: // UTF-8 sort
> + case 5: // UTF-16 sort
> + case 13: // JPEG
> + case 14: // PNG
> + case 27: // BMP
> + case 28: // QuickTime Metadata atom
> + case 70: // BE PointF32
> + case 71: // BE DimensionsF32
> + case 72: // BE RectF32
> + case 79: // AffineTransformF64
> + return AVERROR_PATCHWELCOME;
> + case 1: { // UTF-8
> + int len = data_size < str_size - 1 ? data_size : str_size - 1;
> + memcpy(str, data, len);
> + str[len] = '\0';
> + break;
> + }
> + case 21: { // BE Signed Integer (variable size, not usable for timed
> metadata)
> + int val = 0;
> + switch (data_size) {
> + case 1:
> + val = (int8_t)AV_RB8(data);
> + break;
> + case 2:
> + val = (int16_t)AV_RB16(data);
> + break;
> + case 3:
> + val = ((int32_t)(AV_RB24(data) << 8)) >> 8;
> + break;
> + case 4:
> + val = (int32_t)AV_RB32(data);
> + break;
> + default:
> + return AVERROR(EINVAL);
> + }
> +
> + if (snprintf(str, str_size, "%d", val) >= str_size)
> + return AVERROR(ENOMEM);
> + break;
> + }
> + case 22: { // BE Unsigned Integer (variable size, not usable for
> timed metadata)
> + unsigned int val = 0;
> + switch (data_size) {
> + case 1:
> + val = AV_RB8(data);
> + break;
> + case 2:
> + val = AV_RB16(data);
> + break;
> + case 3:
> + val = AV_RB24(data);
> + break;
> + case 4:
> + val = AV_RB32(data);
> + break;
> + default:
> + return AVERROR(EINVAL);
> + }
> +
> + if (snprintf(str, str_size, "%u", val) >= str_size)
> + return AVERROR(ENOMEM);
> + break;
> + }
> + case 23: { // BE float32
> + float val;
> + if (data_size != 4)
> + return AVERROR(EINVAL);
> +
> + val = av_int2float(AV_RB32(data));
> + if (snprintf(str, str_size, "%f", val) >= str_size)
> + return AVERROR(ENOMEM);
> + break;
> + }
> + case 24: { // BE float64
> + double val;
> + if (data_size != 8)
> + return AVERROR(EINVAL);
> +
> + val = av_int2double(AV_RB64(data));
> + if (snprintf(str, str_size, "%f", val) >= str_size)
> + return AVERROR(ENOMEM);
> + break;
> + }
> + case 65: // 8-bit Signed Integer
> + if (data_size != 1)
> + return AVERROR(EINVAL);
> + if (snprintf(str, str_size, "%d", (int)(int8_t)data[0]) >=
> str_size)
> + return AVERROR(ENOMEM);
> + break;
> + case 66: // BE 16-bit Signed Integer
> + if (data_size != 2)
> + return AVERROR(EINVAL);
> + if (snprintf(str, str_size, "%d", (int)(int16_t)AV_RB16(data)) >=
> str_size)
> + return AVERROR(ENOMEM);
> + break;
> + case 67: // BE 32-bit Signed Integer
> + if (data_size != 4)
> + return AVERROR(EINVAL);
> + if (snprintf(str, str_size, "%d", (int)(int32_t)AV_RB32(data)) >=
> str_size)
> + return AVERROR(ENOMEM);
> + break;
> + case 74: // BE 64-bit Signed Integer
> + if (data_size != 8)
> + return AVERROR(EINVAL);
> + if (snprintf(str, str_size, "%lld", (long
> long)(int64_t)AV_RB64(data)) >= str_size)
> + return AVERROR(ENOMEM);
> + break;
> + case 75: // 8-bit Unsigned Integer
> + if (data_size != 1)
> + return AVERROR(EINVAL);
> + if (snprintf(str, str_size, "%u", (unsigned int)data[0]) >=
> str_size)
> + return AVERROR(ENOMEM);
> + break;
> + case 76: // BE 16-bit Unsigned Integer
> + if (data_size != 2)
> + return AVERROR(EINVAL);
> + if (snprintf(str, str_size, "%u", (unsigned int)AV_RB16(data)) >=
> str_size)
> + return AVERROR(ENOMEM);
> + break;
> + case 77: // BE 32-bit Unsigned Integer
> + if (data_size != 4)
> + return AVERROR(EINVAL);
> + if (snprintf(str, str_size, "%u", (unsigned int)AV_RB32(data)) >=
> str_size)
> + return AVERROR(ENOMEM);
> + break;
> + case 78: // BE 64-bit Unsigned Integer
> + if (data_size != 8)
> + return AVERROR(EINVAL);
> + if (snprintf(str, str_size, "%llu", (unsigned long
> long)AV_RB64(data)) >= str_size)
> + return AVERROR(ENOMEM);
> + break;
> + default:
> + return AVERROR(EINVAL);
> + }
> +
> + return 0;
> +}
> +
> +int av_qtff_convert_str_to_well_known(int data_type, const char *str,
> uint8_t *data, int data_size)
> +{
> + if (!str || !data)
> + return AVERROR(EINVAL);
> +
> + switch (data_type) {
> + case 0: // Reserved
> + case 2: // UTF-16
> + case 3: // S/JIS
> + case 4: // UTF-8 sort
> + case 5: // UTF-16 sort
> + case 13: // JPEG
> + case 14: // PNG
> + case 27: // BMP
> + case 28: // QuickTime Metadata atom
> + case 70: // BE PointF32
> + case 71: // BE DimensionsF32
> + case 72: // BE RectF32
> + case 79: // AffineTransformF64
> + return AVERROR_PATCHWELCOME; // these are defined well-known
> types, but not implemented to be parsed
> + case 1: { // UTF-8
> + int len = strlen(str);
> + if (len > data_size)
> + return AVERROR(ENOMEM);
> + memcpy(data, str, len);
> + return len;
> + }
> + case 21: { // BE Signed Integer (variable size, not usable for timed
> metadata)
> + long long val;
> + char *endptr;
> +
> + val = strtoll(str, &endptr, 10);
> + if (endptr == str || *endptr != '\0')
> + return AVERROR(EINVAL);
> +
> + switch (data_size) {
> + case 1:
> + if (val < INT8_MIN || val > INT8_MAX)
> + return AVERROR(ERANGE);
> + AV_WB8(data, (uint8_t)val);
> + break;
> + case 2:
> + if (val < INT16_MIN || val > INT16_MAX)
> + return AVERROR(ERANGE);
> + AV_WB16(data, (int16_t)val);
> + break;
> + case 3:
> + if (val < -8388608 || val > 8388607) // 24-bit signed range
> + return AVERROR(ERANGE);
> + AV_WB24(data, (int32_t)val);
> + break;
> + case 4:
> + if (val < INT32_MIN || val > INT32_MAX)
> + return AVERROR(ERANGE);
> + AV_WB32(data, (int32_t)val);
> + break;
> + default:
> + return AVERROR(EINVAL);
> + }
> + break;
> + }
> + case 22: { // BE unsigned integer, variable size
> + unsigned long long val;
> + char *endptr;
> +
> + val = strtoull(str, &endptr, 10);
> + if (endptr == str || *endptr != '\0')
> + return AVERROR(EINVAL);
> +
> + switch (data_size) {
> + case 1:
> + if (val > UINT8_MAX)
> + return AVERROR(ERANGE);
> + AV_WB8(data, (uint8_t)val);
> + break;
> + case 2:
> + if (val > UINT16_MAX)
> + return AVERROR(ERANGE);
> + AV_WB16(data, (uint16_t)val);
> + break;
> + case 3:
> + if (val > 16777215) // 24-bit unsigned range
> + return AVERROR(ERANGE);
> + AV_WB24(data, (uint32_t)val);
> + break;
> + case 4:
> + if (val > UINT32_MAX)
> + return AVERROR(ERANGE);
> + AV_WB32(data, (uint32_t)val);
> + break;
> + default:
> + return AVERROR(EINVAL);
> + }
> + break;
> + }
> + case 23: { // BE float32
> + float val;
> + char *endptr;
> +
> + if (data_size != 4)
> + return AVERROR(EINVAL);
> +
> + val = strtof(str, &endptr);
> + if (endptr == str || *endptr != '\0')
> + return AVERROR(EINVAL);
> +
> + AV_WB32(data, av_float2int(val));
> + break;
> + }
> + case 24: { // BE float64
> + double val;
> + char *endptr;
> +
> + if (data_size != 8)
> + return AVERROR(EINVAL);
> +
> + val = strtod(str, &endptr);
> + if (endptr == str || *endptr != '\0')
> + return AVERROR(EINVAL);
> +
> + AV_WB64(data, av_double2int(val));
> + break;
> + }
> + case 65: // 8-bit Signed Integer
> + case 66: // BE 16-bit Signed Integer
> + case 67: // BE 32-bit Signed Integer
> + case 74: { // BE 64-bit Signed Integer
> + long long val;
> + char *endptr;
> + int expected_size = (data_type == 65) ? 1 : (data_type == 66) ? 2
> : (data_type == 67) ? 4 : 8;
> +
> + if (data_size != expected_size)
> + return AVERROR(EINVAL);
> +
> + val = strtoll(str, &endptr, 10);
> + if (endptr == str || *endptr != '\0')
> + return AVERROR(EINVAL);
> +
> + switch (data_type) {
> + case 65:
> + if (val < INT8_MIN || val > INT8_MAX)
> + return AVERROR(ERANGE);
> + AV_WB8(data, (uint8_t)val);
> + break;
> + case 66:
> + if (val < INT16_MIN || val > INT16_MAX)
> + return AVERROR(ERANGE);
> + AV_WB16(data, (int16_t)val);
> + break;
> + case 67:
> + if (val < INT32_MIN || val > INT32_MAX)
> + return AVERROR(ERANGE);
> + AV_WB32(data, (int32_t)val);
> + break;
> + case 74:
> + AV_WB64(data, (int64_t)val);
> + break;
> + }
> + break;
> + }
> + case 75: // 8-bit Unsigned Integer
> + case 76: // BE 16-bit Unsigned Integer
> + case 77: // BE 32-bit Unsigned Integer
> + case 78: { // BE 64-bit Unsigned Integer
> + unsigned long long val;
> + char *endptr;
> + int expected_size = (data_type == 75) ? 1 : (data_type == 76) ? 2
> : (data_type == 77) ? 4 : 8;
> +
> + if (data_size != expected_size)
> + return AVERROR(EINVAL);
> +
> + val = strtoull(str, &endptr, 10);
> + if (endptr == str || *endptr != '\0')
> + return AVERROR(EINVAL);
> +
> + switch (data_type) {
> + case 75:
> + if (val > UINT8_MAX)
> + return AVERROR(ERANGE);
> + AV_WB8(data, (uint8_t)val);
> + break;
> + case 76:
> + if (val > UINT16_MAX)
> + return AVERROR(ERANGE);
> + AV_WB16(data, (uint16_t)val);
> + break;
> + case 77:
> + if (val > UINT32_MAX)
> + return AVERROR(ERANGE);
> + AV_WB32(data, (uint32_t)val);
> + break;
> + case 78:
> + AV_WB64(data, (uint64_t)val);
> + break;
> + }
> + break;
> + }
> + default:
> + return AVERROR(EINVAL);
> + }
> +
> + return data_size;
> +}
> diff --git a/libavutil/qtff.h b/libavutil/qtff.h
> new file mode 100644
> index 0000000000..912ea9e870
> --- /dev/null
> +++ b/libavutil/qtff.h
> @@ -0,0 +1,59 @@
> +/*
> + * copyright (c) 2025 Lukas Holliger
> + *
> + * 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
> + */
> +
> +#ifndef AVUTIL_QTFF_H
> +#define AVUTIL_QTFF_H
> +
> +#include <stdint.h>
> +
> +/**
> + * @file
> + * QuickTime File Format (QTFF) utilities
> + */
> +
> +/**
> + * Convert a QuickTime well-known type to a string
> + *
> + * @param data_type QuickTime metadata data type
> + * @param data Pointer to the binary data
> + * @param data_size Size of the binary data in bytes
> + * @param str Buffer to write the string representation to
> + * @param str_size Size of the output buffer
> + * @return 0 on success, negative AVERROR code on failure
> + *
> + * @see
> https://developer.apple.com/documentation/quicktime-file-format/well-known_types
> + */
> +int av_qtff_convert_well_known_to_str(int data_type, const uint8_t *data,
> int data_size,
> + char *str, int str_size);
> +
> +/**
> + * Convert a string to QuickTime well-known value
> + *
> + * @param data_type QuickTime metadata data type
> + * @param str Input string to convert
> + * @param data Buffer to write the binary data to
> + * @param data_size Size to use for the binary data
> + * @return Number of bytes written on success, negative AVERROR
> code on failure
> + *
> + * @see
> https://developer.apple.com/documentation/quicktime-file-format/well-known_types
> + */
> +int av_qtff_convert_str_to_well_known(int data_type, const char *str,
> uint8_t *data, int data_size);
> +
> +#endif /* AVUTIL_QTFF_H */
> --
> 2.49.1
>
>
> >From 3616592b585440ca4984052e53c85ff5df29f3bf Mon Sep 17 00:00:00 2001
> From: lholliger <lukas@holliger.me>
> Date: Wed, 5 Nov 2025 14:33:22 -0500
> Subject: [PATCH 2/2] libavformat/mov: use qtff decoder util
>
> There was previously a segment here to attempt to decode some of the
> well-known QTFF types but in order to simplify the function and
> implement more types this segment can be replaced with a call to
> the qtff util.
>
> Signed-off-by: lholliger <lukas@holliger.me>
> ---
> libavformat/mov.c | 78 +++++++++++++++++------------------------------
> 1 file changed, 28 insertions(+), 50 deletions(-)
>
> diff --git a/libavformat/mov.c b/libavformat/mov.c
> index 45c562cdc6..9cf62955c2 100644
> --- a/libavformat/mov.c
> +++ b/libavformat/mov.c
> @@ -45,6 +45,7 @@
> #include "libavutil/aes.h"
> #include "libavutil/aes_ctr.h"
> #include "libavutil/pixdesc.h"
> +#include "libavutil/qtff.h"
> #include "libavutil/sha.h"
> #include "libavutil/spherical.h"
> #include "libavutil/stereo3d.h"
> @@ -521,61 +522,38 @@ retry:
> else {
> if (!raw && (data_type == 3 || (data_type == 0 && (langcode <
> 0x400 || langcode == 0x7fff)))) { // MAC Encoded
> mov_read_mac_string(c, pb, str_size, str, str_size_alloc);
> - } else if (data_type == 21) { // BE signed integer, variable size
> - int val = 0;
> - if (str_size == 1)
> - val = (int8_t)avio_r8(pb);
> - else if (str_size == 2)
> - val = (int16_t)avio_rb16(pb);
> - else if (str_size == 3)
> - val = ((int32_t)(avio_rb24(pb)<<8))>>8;
> - else if (str_size == 4)
> - val = (int32_t)avio_rb32(pb);
> - if (snprintf(str, str_size_alloc, "%d", val) >=
> str_size_alloc) {
> - av_log(c->fc, AV_LOG_ERROR,
> - "Failed to store the number (%d) in string.\n",
> val);
> - av_free(str);
> - return AVERROR_INVALIDDATA;
> - }
> - } else if (data_type == 22) { // BE unsigned integer, variable
> size
> - unsigned int val = 0;
> - if (str_size == 1)
> - val = avio_r8(pb);
> - else if (str_size == 2)
> - val = avio_rb16(pb);
> - else if (str_size == 3)
> - val = avio_rb24(pb);
> - else if (str_size == 4)
> - val = avio_rb32(pb);
> - if (snprintf(str, str_size_alloc, "%u", val) >=
> str_size_alloc) {
> - av_log(c->fc, AV_LOG_ERROR,
> - "Failed to store the number (%u) in string.\n",
> val);
> - av_free(str);
> - return AVERROR_INVALIDDATA;
> - }
> - } else if (data_type == 23 && str_size >= 4) { // BE float32
> - float val = av_int2float(avio_rb32(pb));
> - if (snprintf(str, str_size_alloc, "%f", val) >=
> str_size_alloc) {
> - av_log(c->fc, AV_LOG_ERROR,
> - "Failed to store the float32 number (%f) in
> string.\n", val);
> - av_free(str);
> - return AVERROR_INVALIDDATA;
> - }
> - } else if (data_type > 1 && data_type != 4) {
> - // data_type can be 0 if not set at all above. data_type 1
> means
> - // UTF8 and 4 means "UTF8 sort". For any other type (UTF16 or
> e.g.
> - // a picture), don't return it blindly in a string that is
> supposed
> - // to be UTF8 text.
> - av_log(c->fc, AV_LOG_WARNING, "Skipping unhandled metadata %s
> of type %d\n", key, data_type);
> - av_free(str);
> - return 0;
> } else {
> - int ret = ffio_read_size(pb, str, str_size);
> + uint8_t *data_buf = av_malloc(str_size);
> + int ret;
> +
> + if (!data_buf) {
> + av_free(str);
> + return AVERROR(ENOMEM);
> + }
> +
> + ret = ffio_read_size(pb, data_buf, str_size);
> if (ret < 0) {
> + av_free(data_buf);
> + av_free(str);
> + return ret;
> + }
> +
> + // Data types 0 and 4 are technically reserved and a special
> case, but were previously
> + // decoded to UTF-8 here.
> + ret = av_qtff_convert_well_known_to_str(data_type == 0 ||
> data_type == 4 ? 1 : data_type,
> + data_buf, str_size,
> str, str_size_alloc);
> + av_free(data_buf);
> +
> + if (ret == AVERROR_PATCHWELCOME || ret == AVERROR(EINVAL)) {
> + av_log(c->fc, AV_LOG_WARNING, "Skipping unhandled
> metadata %s of type %d\n", key, data_type);
> + av_free(str);
> + return 0;
> + } else if (ret < 0) {
> + av_log(c->fc, AV_LOG_ERROR,
> + "Failed to convert metadata %s of type %d to
> string.\n", key, data_type);
> av_free(str);
> return ret;
> }
> - str[str_size] = 0;
> }
> c->fc->event_flags |= AVFMT_EVENT_FLAG_METADATA_UPDATED;
> av_dict_set(metadata, key, str, 0);
> --
> 2.49.1
>
> _______________________________________________
> ffmpeg-devel mailing list -- ffmpeg-devel@ffmpeg.org
> To unsubscribe send an email to ffmpeg-devel-leave@ffmpeg.org
Why does this need to be in avutil?
Kieran
>
>
_______________________________________________
ffmpeg-devel mailing list -- ffmpeg-devel@ffmpeg.org
To unsubscribe send an email to ffmpeg-devel-leave@ffmpeg.org
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2025-11-05 21:03 UTC | newest]
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2025-11-05 19:37 [FFmpeg-devel] [PATCH] libavutil: add qtff well-known type functions (PR #20846) Lukas via ffmpeg-devel
2025-11-05 21:02 ` [FFmpeg-devel] " Kieran Kunhya via ffmpeg-devel
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