I am wrapping MLT (Media Loving Toolkit) which it seemed quite straightforward with nimterop.
I managed to compile a few examples, but now I am stuck with a problem for some time and I am not managing to find the issue.
The code is here.
The problem that I am having is when I try to compile one of the examples:
$ cd examples
$ nim c -r ex06_playlist
Hint: used config file '/home/jose/.choosenim/toolchains/nim-1.6.0/config/nim.cfg' [Conf]
Hint: used config file '/home/jose/.choosenim/toolchains/nim-1.6.0/config/config.nims' [Conf]
Hint: used config file '/home/jose/src/mlt.nim/examples/config.nims' [Conf]
.............................................................
/home/jose/src/mlt.nim/src/wrapper/mlt.nim(1647, 70) Warning: use `char` or `uint8` instead; cuchar is deprecated [Deprecated]
................................
/home/jose/src/mlt.nim/src/lib/consumer.nim(2, 14) Warning: imported and not used: 'os' [UnusedImport]
.
/home/jose/src/mlt.nim/src/lib/producer.nim(2, 14) Warning: imported and not used: 'os' [UnusedImport]
.
/home/jose/src/mlt.nim/src/lib/filter.nim(2, 14) Warning: imported and not used: 'os' [UnusedImport]
..
/home/jose/src/mlt.nim/src/lib/properties.nim(2, 14) Warning: imported and not used: 'os' [UnusedImport]
/home/jose/src/mlt.nim/src/lib/properties.nim(2, 21) Warning: imported and not used: 'strformat' [UnusedImport]
.
/home/jose/src/mlt.nim/src/lib/service.nim(2, 14) Warning: imported and not used: 'os' [UnusedImport]
.
/home/jose/src/mlt.nim/src/lib/playlist.nim(5, 14) Warning: imported and not used: 'os' [UnusedImport]
/home/jose/src/mlt.nim/src/lib/playlist.nim(5, 21) Warning: imported and not used: 'strformat' [UnusedImport]
CC: ../src/wrapper/mlt.nim
CC: ../src/lib/playlist.nim
CC: ex06_playlist.nim
/home/jose/.cache/nim/ex06_playlist_d/@m..@ssrc@[email protected]:27:31: error: conflicting types for ‘playlist_entry’; have ‘struct playlist_entry’
27 | typedef struct playlist_entry playlist_entry;
| ^~~~~~~~~~~~~~
En el fichero incluido desde /usr/include/mlt-7/framework/mlt.h:50,
desde /home/jose/.cache/nim/ex06_playlist_d/@m..@ssrc@[email protected]:8:
/usr/include/mlt-7/framework/mlt_playlist.h:50:33: nota: previous declaration of ‘playlist_entry’ with type ‘playlist_entry’ {también conocido como ‘struct playlist_entry_s’}
50 | typedef struct playlist_entry_s playlist_entry;
| ^~~~~~~~~~~~~~
/home/jose/.cache/nim/ex06_playlist_d/@m..@ssrc@[email protected]:32:33: error: conflicting types for ‘playlist_entry’; have ‘struct playlist_entry’
32 | typedef struct playlist_entry playlist_entry;
| ^~~~~~~~~~~~~~
En el fichero incluido desde /usr/include/mlt-7/framework/mlt.h:50,
desde /home/jose/.cache/nim/ex06_playlist_d/@m..@ssrc@[email protected]:8:
/usr/include/mlt-7/framework/mlt_playlist.h:50:33: nota: previous declaration of ‘playlist_entry’ with type ‘playlist_entry’ {también conocido como ‘struct playlist_entry_s’}
50 | typedef struct playlist_entry_s playlist_entry;
| ^~~~~~~~~~~~~~
Error: execution of an external compiler program 'gcc -c -w -fmax-errors=3 -I/usr/include/mlt-7/framework -I/home/jose/.choosenim/toolchains/nim-1.6.0/lib -I/home/jose/src/mlt.nim/examples -o /home/jose/.cache/nim/ex06_playlist_d/@m..@ssrc@[email protected] /home/jose/.cache/nim/ex06_playlist_d/@m..@ssrc@[email protected]' failed with exit code: 1
/home/jose/.cache/nim/ex06_playlist_d/@mex06_playlist.nim.c:35:31: error: conflicting types for ‘playlist_entry’; have ‘struct playlist_entry’
35 | typedef struct playlist_entry playlist_entry;
| ^~~~~~~~~~~~~~
En el fichero incluido desde /usr/include/mlt-7/framework/mlt.h:50,
desde /home/jose/.cache/nim/ex06_playlist_d/@mex06_playlist.nim.c:8:
/usr/include/mlt-7/framework/mlt_playlist.h:50:33: nota: previous declaration of ‘playlist_entry’ with type ‘playlist_entry’ {también conocido como ‘struct playlist_entry_s’}
50 | typedef struct playlist_entry_s playlist_entry;
| ^~~~~~~~~~~~~~
If I look at the header and the generated code I understand why it fails. But I don't know how to avoid it.
I would appreciate some help here
Fixed by replacing in mlt.nim:
type
...
playlist_entry* {.importc, impmltHdr.} = playlist_entry_s
type
...
playlist_entry* {.importc, impmltHdr.} = object
Just for fun tried to see how Futhark would fare. Seems to compile fine at least. Nicked the Nim-wrapping procedures from you, but the C -> Nim wrapping is done by Futhark:
import futhark
{.passC: "-I/usr/include/mlt/framework".}
{.passL: "-lmlt".}
type Playlist = pointer
proc mltfactoryclose*(): void {.cdecl, importc: "mlt_factory_close".}
proc mltplaylistinit*(): Playlist {.cdecl, importc: "mlt_playlist_init".}
importc:
path "/usr/lib/gcc/x86_64-pc-linux-gnu/11.1.0/include"
path "/usr/lib/gcc/x86_64-pc-linux-gnu/11.1.0/include-fixed"
path "/usr/include"
"mlt/framework/mlt.h"
"mlt/framework/mlt_consumer.h"
"mlt/framework/mlt_profile.h"
"mlt/framework/mlt_playlist.h"
"mlt/framework/mlt_producer.h"
"mlt/framework/mlt_properties.h"
"mlt/framework/mlt_factory.h"
"mlt/framework/mlt_repository.h"
"mlt/framework/mlt_service.h"
"mlt/framework/mlt_filter.h"
rename mlt_profile, Profile
rename mlt_playlist, Playlist
rename mlt_producer, Producer
rename mlt_repository, Repository
rename mlt_consumer, Consumer
rename mlt_service, Service
rename mlt_filter, Filter
rename mlt_properties, Properties
#rename mlt_factory_close, closeFactory
import os
proc newProfile(): Profile = mlt_profile_init(nil)
proc newPlaylist(): Playlist = mlt_playlist_init()
proc initFactory*(): Repository =
mlt_factory_init(nil)
proc initFactory*(directory: string): Repository =
mlt_factory_init(directory.cstring)
proc newFactoryProducer(profile: Profile; service: string = "loader";
resource: string = ""): Producer =
mlt_factory_producer(profile, service.cstring, resource.cstring)
proc append*(self: Playlist; producer: Producer) =
let res = mlt_playlist_append(self, producer)
if res > 0:
quit("Unable to append producer to the playlist")
proc close*(self: Playlist) =
mlt_playlist_close(self)
proc close*(self: Producer) =
mlt_producer_close(self)
proc newFactoryConsumer*(profile: Profile; service: string = "sdl2";
input: string = ""): Consumer =
if input == "":
mlt_factory_consumer(profile, service.cstring, nil)
else:
mlt_factory_consumer(profile, service.cstring, input.cstring)
proc connect*(self: Consumer, producer: Service) =
let res = mlt_consumer_connect(self, producer).int
if res > 0:
quit("mlt_consumer_connect returned >0")
proc connect*(self:Filter; producer: Service; index:int = 0) =
let res = mlt_filter_connect(self, producer, index.cint)
if res > 0:
quit("""mlt_consumer_connect returned >0""")
proc newFactoryFilter*(profile: Profile; name: string; input: string = "" ): Filter =
mlt_factory_filter(profile, name.cstring, input.cstring)
proc set*(self: Properties; name: string; value: float) =
let res = mlt_properties_set_double(self, name.cstring, value.cdouble)
if res > 0:
quit("""unable to set property "{name}" """)
proc set*(self: Properties; name, value: string) =
let res = mlt_properties_set_string(self, name.cstring, value.cstring)
if res > 0:
quit("""unable to set property "{name}" """)
converter toService*(self: Filter): Service =
mlt_filter_service(self)
converter toProperties*(self: Service): Properties =
mlt_service_properties(self)
converter toProperties*(self: Filter): Properties =
self.toService.toProperties
converter toService*(self:Producer):Service =
## Get the parent service object.
mlt_producer_service(self)
proc `[]=`*[T: float or string](self: Properties; name: string; value: T) =
set(self, name, value)
proc `>`*(self: Consumer, producer: Service) =
connect(self, producer)
proc start*(self: Consumer) =
let res = mlt_consumer_start(self).int
if res > 0:
quit("""failed to start the consumer""")
proc isStopped*(self: Consumer): bool =
let res = mlt_consumer_is_stopped (self)
if res == 0:
return true
return false
proc close*(a: Consumer) =
mlt_consumer_close(a)
proc close*(a: Filter) =
mlt_filter_close(a)
proc closeFactory*() =
mlt_factory_close()
# Create a playlist
var p:Profile = newProfile()
var pl = newPlaylist()
var clip1 = newFactoryProducer(p, resource = "avformat:/home/jose/Descargas/sygic.mp4")
pl.append(clip1)
close(clip1)
var clip2 = newFactoryProducer(p, resource = "color:red")
pl.append(clip2)
close(clip2)
var f:Repository = initFactory("/usr/lib/mlt-7")
if f == nil:
quit("""mlt_factory_init returned "nil"""")
# Create the default consumer
var hello:Consumer = newFactoryConsumer(p, "sdl2")
if hello == nil:
quit("""mlt_factory_consumer returned "nil"""")
# Create via the default producer
var world:Producer = newFactoryProducer(p, resource = "avformat:/home/jose/Descargas/sygic.mp4")
# Connect the producer to the consumer
if world == nil:
quit("""mlt_factory_producer returned "nil"""")
connect( hello, mlt_producer_service( world ) )
var filter = newFactoryFilter(p, "frei0r.pixeliz0r")
set(filter, "BlockSizeX", 0.1 )
set(filter, "BlockSizeY", 0.1 )
filter["BlockSizeY"] = 0.2
hello > filter #connect( hello, filter)
connect( filter, world )
# Start the consumer
start(hello)
while isStopped(hello):
sleep(1)
# Closing everything
close( hello )
close( filter )
close( world )
closeFactory()
connect( hello, filter )
connect( filter, world )
# Start the consumer
start(hello)
while isStopped(hello):
sleep(1)
# Closing everything
close( hello )
close( filter )
close( world )
closeFactory()
There seems to be a little bug with varargs in Futhark, that's why it has those procedures defined at the top (and the Playlist = pointer type at the very top). Have to look into that..