Question

EDIT
I have check the execution and found that the error is not (yet) at the swscale point. My current issue is that the JPG image is not found:
No such file or directory
when doing the avformat_open_input(&pFormatCtx, imageFileName, NULL, NULL);
Before you tell me I need to register anything, I can tell I already did (I updated the code below).
I also added the Android permission to access the external storage (I don’t think it is related to Android since I can already write to the /mnt/sdcard/ where the image is also located)
END EDIT

I have been through several tutorials (including the few posted from SO, i.e. http://dranger.com/ffmpeg/, how to compile ffmpeg for Android…,been through dolphin-player source code). Here is what I have:
. Compiled ffmpeg for android
. Ran basic tutorials using NDK to create a dummy video on my android device
. been able to generate a MPEG2 video from images on Ubuntu using a modified version of dummy video code above and a lot of Googling
. running the new code on Android device gives a green screen video (duration 1 sec whatever the number of frames I encode)

I saw another post about iPhone in a similar situation that mentioned the ARM processor optimization could be the culprit. I tried a few ldextra-flags (-arch armv7-a and similar) to no success.

I include at the end the code that loads the image. Is there something different to do on Android than on linux? Is my ffmpeg build not correct for Android video encoding?

void copyFrame(AVCodecContext *destContext, AVFrame* dest,
            AVCodecContext *srcContext, AVFrame* source) {
struct SwsContext *swsContext;
swsContext = sws_getContext(srcContext->width, srcContext->height, srcContext->pix_fmt,
                destContext->width, destContext->height, destContext->pix_fmt,
                SWS_FAST_BILINEAR, NULL, NULL, NULL);
sws_scale(swsContext, source->data, source->linesize, 0, srcContext->height, dest->data, dest->linesize);
sws_freeContext(swsContext);
}

int loadFromFile(const char* imageFileName, AVFrame* realPicture, AVCodecContext* videoContext) {
AVFormatContext *pFormatCtx = NULL;
avcodec_register_all();
av_register_all();

int ret = avformat_open_input(&pFormatCtx, imageFileName, NULL, NULL);
if (ret != 0) {
    // ERROR hapening here
    // Can't open image file. Use strerror(AVERROR(ret))) for details
    return ERR_CANNOT_OPEN_IMAGE;
}

AVCodecContext *pCodecCtx;

pCodecCtx = pFormatCtx->streams[0]->codec;
pCodecCtx->width = W_VIDEO;
pCodecCtx->height = H_VIDEO;
pCodecCtx->pix_fmt = PIX_FMT_YUV420P;

// Find the decoder for the video stream
AVCodec *pCodec = avcodec_find_decoder(pCodecCtx->codec_id);
if (!pCodec) {
    // Codec not found
    return ERR_CODEC_NOT_FOUND;
}

// Open codec
if (avcodec_open(pCodecCtx, pCodec) < 0) {
    // Could not open codec
    return ERR_CANNOT_OPEN_CODEC;
}

// 
AVFrame *pFrame;

pFrame = avcodec_alloc_frame();

if (!pFrame) {
    // Can't allocate memory for AVFrame
    return ERR_CANNOT_ALLOC_MEM;
}

int frameFinished;
int numBytes;

// Determine required buffer size and allocate buffer
numBytes = avpicture_get_size(PIX_FMT_YUV420P, pCodecCtx->width, pCodecCtx->height);
uint8_t *buffer = (uint8_t *) av_malloc(numBytes * sizeof (uint8_t));

avpicture_fill((AVPicture *) pFrame, buffer, PIX_FMT_YUV420P, pCodecCtx->width, pCodecCtx->height);
AVPacket packet;
int res = 0;
while (av_read_frame(pFormatCtx, &packet) >= 0) {
    if (packet.stream_index != 0)
        continue;

    ret = avcodec_decode_video2(pCodecCtx, pFrame, &frameFinished, &packet);
    if (ret > 0) {
        // now, load the useful info into realPicture
        copyFrame(videoContext, realPicture, pCodecCtx, pFrame);
        // Free the packet that was allocated by av_read_frame
        av_free_packet(&packet);
        return 0;
    } else {
        // Error decoding frame. Use strerror(AVERROR(ret))) for details
        res = ERR_DECODE_FRAME;
    }
}
av_free(pFrame);

// close codec
avcodec_close(pCodecCtx);

// Close the image file
av_close_input_file(pFormatCtx);

return res;
}

Some ./configure options:
--extra-cflags="-O3 -fpic -DANDROID -DHAVE_SYS_UIO_H=1 -Dipv6mr_interface=ipv6mr_ifindex -fasm -Wno-psabi -fno-short-enums -fno-strict-aliasing -finline-limit=300 -mfloat-abi=softfp -mfpu=vfp -marm -march=armv7-a -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE"

--extra-ldflags="-Wl,-rpath-link=$PLATFORM/usr/lib -L$PLATFORM/usr/lib -nostdlib -lc -lm -ldl -llog"

--arch=armv7-a --enable-armv5te --enable-armv6 --enable-armvfp --enable-memalign-hack

Answer 1

The code above is actually working. I tried on other devices (Samsung Galaxy Tab 7) and it is fine. The issue could be due to the cyanomodgen or specific Android version.