[FFmpeg-devel] [PATCH] options_table: replace INT64_MAX with a sligthly smaller value

Andreas Cadhalpun andreas.cadhalpun at googlemail.com
Sat Nov 19 15:01:54 EET 2016


On 19.11.2016 01:39, Michael Niedermayer wrote:
> On Fri, Nov 18, 2016 at 11:06:56PM +0100, Andreas Cadhalpun wrote:
>> AVOption.max is a double, which has not enough precision for INT64_MAX.
>>
>> It gets interpreted as INT64_MIN, when converted back to int64_t.
>>
>> Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun at googlemail.com>
>> ---
>>  libavcodec/options_table.h | 10 ++++++----
>>  1 file changed, 6 insertions(+), 4 deletions(-)
>>
>> diff --git a/libavcodec/options_table.h b/libavcodec/options_table.h
>> index 48de667..f117ce4 100644
>> --- a/libavcodec/options_table.h
>> +++ b/libavcodec/options_table.h
>> @@ -41,8 +41,10 @@
>>  
>>  #define AV_CODEC_DEFAULT_BITRATE 200*1000
>>  
>> +#define FF_INT64_MAX (INT64_MAX - 0x1000)
> 
> Missing documentation

Added a comment.

>> +
>>  static const AVOption avcodec_options[] = {
>> -{"b", "set bitrate (in bits/s)", OFFSET(bit_rate), AV_OPT_TYPE_INT64, {.i64 = AV_CODEC_DEFAULT_BITRATE }, 0, INT64_MAX, A|V|E},
>> +{"b", "set bitrate (in bits/s)", OFFSET(bit_rate), AV_OPT_TYPE_INT64, {.i64 = AV_CODEC_DEFAULT_BITRATE }, 0, FF_INT64_MAX, A|V|E},
>>  {"ab", "set bitrate (in bits/s)", OFFSET(bit_rate), AV_OPT_TYPE_INT64, {.i64 = 128*1000 }, 0, INT_MAX, A|E},
>>  {"bt", "Set video bitrate tolerance (in bits/s). In 1-pass mode, bitrate tolerance specifies how far "
>>         "ratecontrol is willing to deviate from the target average bitrate value. This is not related "
>> @@ -444,11 +446,11 @@ static const AVOption avcodec_options[] = {
>>  #if FF_API_PRIVATE_OPT
>>  {"min_prediction_order", NULL, OFFSET(min_prediction_order), AV_OPT_TYPE_INT, {.i64 = -1 }, INT_MIN, INT_MAX, A|E},
>>  {"max_prediction_order", NULL, OFFSET(max_prediction_order), AV_OPT_TYPE_INT, {.i64 = -1 }, INT_MIN, INT_MAX, A|E},
>> -{"timecode_frame_start", "GOP timecode frame start number, in non-drop-frame format", OFFSET(timecode_frame_start), AV_OPT_TYPE_INT64, {.i64 = -1 }, -1, INT64_MAX, V|E},
>> +{"timecode_frame_start", "GOP timecode frame start number, in non-drop-frame format", OFFSET(timecode_frame_start), AV_OPT_TYPE_INT64, {.i64 = -1 }, -1, FF_INT64_MAX, V|E},
>>  #endif
> 
>>  {"bits_per_raw_sample", NULL, OFFSET(bits_per_raw_sample), AV_OPT_TYPE_INT, {.i64 = DEFAULT }, 0, INT_MAX},
>> -{"channel_layout", NULL, OFFSET(channel_layout), AV_OPT_TYPE_INT64, {.i64 = DEFAULT }, 0, INT64_MAX, A|E|D, "channel_layout"},
>> +{"channel_layout", NULL, OFFSET(channel_layout), AV_OPT_TYPE_INT64, {.i64 = DEFAULT }, 0, FF_INT64_MAX, A|E|D, "channel_layout"},
>> -{"request_channel_layout", NULL, OFFSET(request_channel_layout), AV_OPT_TYPE_INT64, {.i64 = DEFAULT }, 0, INT64_MAX, A|D, "request_channel_layout"},
>> +{"request_channel_layout", NULL, OFFSET(request_channel_layout), AV_OPT_TYPE_INT64, {.i64 = DEFAULT }, 0, FF_INT64_MAX, A|D, "request_channel_layout"},
> 
> this doesnt feel right
> layout is not a scalar

Then why is it limited to positive values?
Currently setting either of those to "max" will actually cause them to be set to INT64_MIN.

Anyway, I dropped this part. New patch attached.

Best regards,
Andreas

-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0001-options_table-replace-INT64_MAX-with-a-sligthly-smal.patch
Type: text/x-diff
Size: 2524 bytes
Desc: not available
URL: <http://ffmpeg.org/pipermail/ffmpeg-devel/attachments/20161119/bbe96b13/attachment.patch>


More information about the ffmpeg-devel mailing list