[FFmpeg-devel] [PATCH 2/4] libavdevice/decklink: add support for -sources and -sinks arguments

Devin Heitmueller dheitmueller at ltnglobal.com
Wed Oct 4 23:56:33 EEST 2017


> On Sep 30, 2017, at 4:02 PM, Marton Balint <cus at passwd.hu> wrote:
> 
> 
> 
> On Tue, 26 Sep 2017, Devin Heitmueller wrote:
> 
>> Add support for enumerating the sources/sinks via the ffmpeg
>> command line options, as opposed to having to create a real pipeline
>> and use the "-list_devices" option which does exit() after dumping
>> out the options.
>> 
>> Note that this patch preserves the existing "-list_devices" option,
>> but now shares common code for the actual enumeration.
>> 
>> Signed-off-by: Devin Heitmueller <dheitmueller at ltnglobal.com>
>> ---
>> libavdevice/decklink_common.cpp | 52 +++++++++++++++++++++++++++++++++++++----
>> libavdevice/decklink_common.h   |  2 +-
>> libavdevice/decklink_dec.cpp    | 22 ++++++++++++++++-
>> libavdevice/decklink_dec.h      |  1 +
>> libavdevice/decklink_dec_c.c    |  1 +
>> libavdevice/decklink_enc.cpp    | 22 ++++++++++++++++-
>> libavdevice/decklink_enc.h      |  1 +
>> libavdevice/decklink_enc_c.c    |  1 +
>> 8 files changed, 95 insertions(+), 7 deletions(-)
>> 
>> diff --git a/libavdevice/decklink_common.cpp b/libavdevice/decklink_common.cpp
>> index 7745575d0e..86d6fbb74b 100644
>> --- a/libavdevice/decklink_common.cpp
>> +++ b/libavdevice/decklink_common.cpp
>> @@ -37,6 +37,7 @@ extern "C" {
>> #include "libavutil/imgutils.h"
>> #include "libavutil/intreadwrite.h"
>> #include "libavutil/bswap.h"
>> +#include "avdevice.h"
>> }
>> #include "decklink_common.h"
>> @@ -261,24 +262,67 @@ int ff_decklink_set_format(AVFormatContext *avctx, decklink_direction_t directio
>>    return ff_decklink_set_format(avctx, 0, 0, 0, 0, AV_FIELD_UNKNOWN, direction, num);
>> }
>> -int ff_decklink_list_devices(AVFormatContext *avctx)
>> +int ff_decklink_list_devices(AVFormatContext *avctx,
>> +			     struct AVDeviceInfoList *device_list,
>> +			     int show_inputs, int show_outputs)
>> {
>>    IDeckLink *dl = NULL;
>>    IDeckLinkIterator *iter = CreateDeckLinkIteratorInstance();
>> +    int ret = 0;
>> +
>>    if (!iter) {
>>        av_log(avctx, AV_LOG_ERROR, "Could not create DeckLink iterator\n");
>>        return AVERROR(EIO);
>>    }
>> -    av_log(avctx, AV_LOG_INFO, "Blackmagic DeckLink devices:\n");
>> +
>>    while (iter->Next(&dl) == S_OK) {
> 
> This probably needs an additional && ret == 0 condition, if there was an ENOMEM error, you want to return instantly instead of trying with the next device, and ignoring the ENOMEM.
> 
>> +        IDeckLinkOutput *output_config;
>> +        IDeckLinkInput *input_config;
>>        const char *displayName;
>> +        AVDeviceInfo *new_device = NULL;
>> +        int add = 0;
>> +
>>        ff_decklink_get_display_name(dl, &displayName);
>> -        av_log(avctx, AV_LOG_INFO, "\t'%s'\n", displayName);
>> +
>> +        if (show_outputs) {
>> +            if (dl->QueryInterface(IID_IDeckLinkOutput, (void **)&output_config) == S_OK) {
>> +                output_config->Release();
>> +                add = 1;
>> +            }
>> +        }
>> +
>> +        if (show_inputs) {
>> +            if (dl->QueryInterface(IID_IDeckLinkInput, (void **)&input_config) == S_OK) {
>> +                input_config->Release();
>> +                add = 1;
>> +            }
>> +        }
>> +
>> +        if (add == 1) {
>> +            new_device = (AVDeviceInfo *) av_mallocz(sizeof(AVDeviceInfo));
>> +            if (!new_device) {
>> +                ret = AVERROR(ENOMEM);
>> +                goto next;
>> +            }
>> +            new_device->device_name = av_strdup(displayName);
>> +            new_device->device_description = av_strdup(displayName);
>> +            if (!new_device->device_description || !new_device->device_name) {
> 
> you might leak device_name here.
> 
>> +                ret = AVERROR(ENOMEM);
>> +                goto next;
>> +            }
>> +
>> +            if ((ret = av_dynarray_add_nofree(&device_list->devices,
>> +                                              &device_list->nb_devices, new_device)) < 0) {
> 
> you should free the struct on error here I think
> 
>> +                goto next;
>> +            }
>> +        }
>> +
>> +    next:
>>        av_free((void *) displayName);
> 
> av_freep
> 
>>        dl->Release();
>>    }
>>    iter->Release();
>> -    return 0;
>> +    return ret;
>> }
>> int ff_decklink_list_formats(AVFormatContext *avctx, decklink_direction_t direction)
>> diff --git a/libavdevice/decklink_common.h b/libavdevice/decklink_common.h
>> index 749eb0f8b8..f81b33ada4 100644
>> --- a/libavdevice/decklink_common.h
>> +++ b/libavdevice/decklink_common.h
>> @@ -135,7 +135,7 @@ static const BMDVideoConnection decklink_video_connection_map[] = {
>> HRESULT ff_decklink_get_display_name(IDeckLink *This, const char **displayName);
>> int ff_decklink_set_format(AVFormatContext *avctx, int width, int height, int tb_num, int tb_den, enum AVFieldOrder field_order, decklink_direction_t direction = DIRECTION_OUT, int num = 0);
>> int ff_decklink_set_format(AVFormatContext *avctx, decklink_direction_t direction, int num);
>> -int ff_decklink_list_devices(AVFormatContext *avctx);
>> +int ff_decklink_list_devices(AVFormatContext *avctx, struct AVDeviceInfoList *device_list, int show_inputs, int show_outputs);
>> int ff_decklink_list_formats(AVFormatContext *avctx, decklink_direction_t direction = DIRECTION_OUT);
>> void ff_decklink_cleanup(AVFormatContext *avctx);
>> int ff_decklink_init_device(AVFormatContext *avctx, const char* name);
>> diff --git a/libavdevice/decklink_dec.cpp b/libavdevice/decklink_dec.cpp
>> index c271ff3639..cb282055c6 100644
>> --- a/libavdevice/decklink_dec.cpp
>> +++ b/libavdevice/decklink_dec.cpp
>> @@ -38,6 +38,7 @@ extern "C" {
>> #include "libavutil/time.h"
>> #include "libavutil/mathematics.h"
>> #include "libavutil/reverse.h"
>> +#include "avdevice.h"
>> #if CONFIG_LIBZVBI
>> #include <libzvbi.h>
>> #endif
>> @@ -647,7 +648,21 @@ av_cold int ff_decklink_read_header(AVFormatContext *avctx)
>> 
>>    /* List available devices. */
>>    if (ctx->list_devices) {
>> -        ff_decklink_list_devices(avctx);
>> +        struct AVDeviceInfoList *device_list = NULL;
>> +        int ret;
>> +
>> +        device_list = (struct AVDeviceInfoList *) av_mallocz(sizeof(AVDeviceInfoList));
>> +        if (!device_list)
>> +            return AVERROR(ENOMEM);
>> +
>> +        ret = ff_decklink_list_devices(avctx, device_list, 1, 0);
>> +        if (ret == 0) {
>> +            av_log(avctx, AV_LOG_INFO, "Blackmagic DeckLink input devices:\n");
>> +            for (int i = 0; i < device_list->nb_devices; i++) {
>> +                av_log(avctx, AV_LOG_INFO, "\t'%s'\n", device_list->devices[i]->device_name);
>> +            }
>> +        }
>> +        avdevice_free_list_devices(&device_list);
>>        return AVERROR_EXIT;
>>    }
>> @@ -810,4 +825,9 @@ int ff_decklink_read_packet(AVFormatContext *avctx, AVPacket *pkt)
>>    return 0;
>> }
>> +int ff_decklink_list_input_devices(AVFormatContext *avctx, struct AVDeviceInfoList *device_list)
>> +{
>> +    return ff_decklink_list_devices(avctx, device_list, 1, 0);
>> +}
>> +
>> } /* extern "C" */
>> diff --git a/libavdevice/decklink_dec.h b/libavdevice/decklink_dec.h
>> index 9b71870deb..fbfbe6280e 100644
>> --- a/libavdevice/decklink_dec.h
>> +++ b/libavdevice/decklink_dec.h
>> @@ -29,6 +29,7 @@ extern "C" {
>> int ff_decklink_read_header(AVFormatContext *avctx);
>> int ff_decklink_read_packet(AVFormatContext *avctx, AVPacket *pkt);
>> int ff_decklink_read_close(AVFormatContext *avctx);
>> +int ff_decklink_list_input_devices(AVFormatContext *avctx, struct AVDeviceInfoList *device_list);
>> #ifdef __cplusplus
>> } /* extern "C" */
>> diff --git a/libavdevice/decklink_dec_c.c b/libavdevice/decklink_dec_c.c
>> index e2118a619c..992c21a160 100644
>> --- a/libavdevice/decklink_dec_c.c
>> +++ b/libavdevice/decklink_dec_c.c
>> @@ -83,6 +83,7 @@ AVInputFormat ff_decklink_demuxer = {
>>    .flags          = AVFMT_NOFILE,
>>    .priv_class     = &decklink_demuxer_class,
>>    .priv_data_size = sizeof(struct decklink_cctx),
>> +    .get_device_list = ff_decklink_list_input_devices,
>>    .read_header   = ff_decklink_read_header,
>>    .read_packet   = ff_decklink_read_packet,
>>    .read_close    = ff_decklink_read_close,
>> diff --git a/libavdevice/decklink_enc.cpp b/libavdevice/decklink_enc.cpp
>> index 25ce7d026c..0f654faa19 100644
>> --- a/libavdevice/decklink_enc.cpp
>> +++ b/libavdevice/decklink_enc.cpp
>> @@ -33,6 +33,7 @@ extern "C" {
>> extern "C" {
>> #include "libavformat/avformat.h"
>> #include "libavutil/imgutils.h"
>> +#include "avdevice.h"
>> }
>> #include "decklink_common.h"
>> @@ -337,7 +338,21 @@ av_cold int ff_decklink_write_header(AVFormatContext *avctx)
>> 
>>    /* List available devices. */
>>    if (ctx->list_devices) {
>> -        ff_decklink_list_devices(avctx);
>> +        struct AVDeviceInfoList *device_list = NULL;
>> +        int ret;
>> +
>> +        device_list = (struct AVDeviceInfoList *) av_mallocz(sizeof(AVDeviceInfoList));
>> +        if (!device_list)
>> +            return AVERROR(ENOMEM);
>> +
>> +        ret = ff_decklink_list_devices(avctx, device_list, 0, 1);
>> +        if (ret == 0) {
>> +            av_log(avctx, AV_LOG_INFO, "Blackmagic DeckLink output devices:\n");
>> +            for (int i = 0; i < device_list->nb_devices; i++) {
>> +                av_log(avctx, AV_LOG_INFO, "\t'%s'\n", device_list->devices[i]->device_name);
>> +            }
>> +        }
>> +        avdevice_free_list_devices(&device_list);
> 
> This code can be factorized among input and output.
> 
>>        return AVERROR_EXIT;
>>    }
>> @@ -400,4 +415,9 @@ int ff_decklink_write_packet(AVFormatContext *avctx, AVPacket *pkt)
>>    return AVERROR(EIO);
>> }
>> +int ff_decklink_list_output_devices(AVFormatContext *avctx, struct AVDeviceInfoList *device_list)
>> +{
>> +    return ff_decklink_list_devices(avctx, device_list, 0, 1);
>> +}
>> +
>> } /* extern "C" */
>> diff --git a/libavdevice/decklink_enc.h b/libavdevice/decklink_enc.h
>> index 5ffc05cd68..39237673b4 100644
>> --- a/libavdevice/decklink_enc.h
>> +++ b/libavdevice/decklink_enc.h
>> @@ -29,6 +29,7 @@ extern "C" {
>> int ff_decklink_write_header(AVFormatContext *avctx);
>> int ff_decklink_write_packet(AVFormatContext *avctx, AVPacket *pkt);
>> int ff_decklink_write_trailer(AVFormatContext *avctx);
>> +int ff_decklink_list_output_devices(AVFormatContext *avctx, struct AVDeviceInfoList *device_list);
>> #ifdef __cplusplus
>> } /* extern "C" */
>> diff --git a/libavdevice/decklink_enc_c.c b/libavdevice/decklink_enc_c.c
>> index 03734f8507..360535cfda 100644
>> --- a/libavdevice/decklink_enc_c.c
>> +++ b/libavdevice/decklink_enc_c.c
>> @@ -49,6 +49,7 @@ AVOutputFormat ff_decklink_muxer = {
>>    .video_codec    = AV_CODEC_ID_WRAPPED_AVFRAME,
>>    .subtitle_codec = AV_CODEC_ID_NONE,
>>    .flags          = AVFMT_NOFILE,
>> +    .get_device_list = ff_decklink_list_output_devices,
>>    .priv_class     = &decklink_muxer_class,
>>    .priv_data_size = sizeof(struct decklink_cctx),
>>    .write_header   = ff_decklink_write_header,
>> -- 
>> 2.13.2
>> 
> 
> Regards,
> Marton

Sorry for the delayed reply.  I will submit updated patches this week that reflect the changes you have requested.

Thanks,

Devin


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